chore: regenerate README (#986)

This PR was generated using Autosynth. 🌈


<details><summary>Log from Synthtool</summary>

```
2020-12-01 17:06:57,202 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-bigquery/.github/readme/synth.py.
On branch autosynth-readme
nothing to commit, working tree clean
2020-12-01 17:06:58,236 synthtool [DEBUG] > Wrote metadata to .github/readme/synth.metadata/synth.metadata.

```
</details>

Full log will be available here:
https://source.cloud.google.com/results/invocations/304c654b-d069-4a1a-b811-83912b153365/targets

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.github/readme/synth.metadata/synth.metadata

@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-bigquery.git",
-        "sha": "5b0c7a2fd80f571b3b128b158c403673cca722cb"
+        "sha": "cf36b82ef9bc0849a87b717c099321915a76b967"
       }
     },
     {

README.md

@@ -187,6 +187,7 @@ has instructions for running the samples.
 | Query External Sheets Temp | [source code](https://github.com/googleapis/java-bigquery/blob/master/samples/snippets/src/main/java/com/example/bigquery/QueryExternalSheetsTemp.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-bigquery&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/bigquery/QueryExternalSheetsTemp.java) |
 | Query External Table Aws | [source code](https://github.com/googleapis/java-bigquery/blob/master/samples/snippets/src/main/java/com/example/bigquery/QueryExternalTableAws.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-bigquery&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/bigquery/QueryExternalTableAws.java) |
 | Query Large Results | [source code](https://github.com/googleapis/java-bigquery/blob/master/samples/snippets/src/main/java/com/example/bigquery/QueryLargeResults.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-bigquery&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/bigquery/QueryLargeResults.java) |
+| Query Materialized View | [source code](https://github.com/googleapis/java-bigquery/blob/master/samples/snippets/src/main/java/com/example/bigquery/QueryMaterializedView.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-bigquery&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/bigquery/QueryMaterializedView.java) |
 | Query Pagination | [source code](https://github.com/googleapis/java-bigquery/blob/master/samples/snippets/src/main/java/com/example/bigquery/QueryPagination.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-bigquery&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/bigquery/QueryPagination.java) |
 | Query Partitioned Table | [source code](https://github.com/googleapis/java-bigquery/blob/master/samples/snippets/src/main/java/com/example/bigquery/QueryPartitionedTable.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-bigquery&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/bigquery/QueryPartitionedTable.java) |
 | Query Script | [source code](https://github.com/googleapis/java-bigquery/blob/master/samples/snippets/src/main/java/com/example/bigquery/QueryScript.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-bigquery&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/bigquery/QueryScript.java) |
@@ -216,6 +217,7 @@ has instructions for running the samples.
 | Update Dataset Description | [source code](https://github.com/googleapis/java-bigquery/blob/master/samples/snippets/src/main/java/com/example/bigquery/UpdateDatasetDescription.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-bigquery&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/bigquery/UpdateDatasetDescription.java) |
 | Update Dataset Expiration | [source code](https://github.com/googleapis/java-bigquery/blob/master/samples/snippets/src/main/java/com/example/bigquery/UpdateDatasetExpiration.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-bigquery&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/bigquery/UpdateDatasetExpiration.java) |
 | Update Dataset Partition Expiration | [source code](https://github.com/googleapis/java-bigquery/blob/master/samples/snippets/src/main/java/com/example/bigquery/UpdateDatasetPartitionExpiration.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-bigquery&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/bigquery/UpdateDatasetPartitionExpiration.java) |
+| Update Iam Policy | [source code](https://github.com/googleapis/java-bigquery/blob/master/samples/snippets/src/main/java/com/example/bigquery/UpdateIamPolicy.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-bigquery&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/bigquery/UpdateIamPolicy.java) |
 | Update Model Description | [source code](https://github.com/googleapis/java-bigquery/blob/master/samples/snippets/src/main/java/com/example/bigquery/UpdateModelDescription.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-bigquery&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/bigquery/UpdateModelDescription.java) |
 | Update Routine | [source code](https://github.com/googleapis/java-bigquery/blob/master/samples/snippets/src/main/java/com/example/bigquery/UpdateRoutine.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-bigquery&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/bigquery/UpdateRoutine.java) |
 | Update Table Cmek | [source code](https://github.com/googleapis/java-bigquery/blob/master/samples/snippets/src/main/java/com/example/bigquery/UpdateTableCmek.java) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/java-bigquery&page=editor&open_in_editor=samples/snippets/src/main/java/com/example/bigquery/UpdateTableCmek.java) |