chore: regenerate README (#947)

This PR was generated using Autosynth. 🌈


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

```
2020-11-14 01:17:14,982 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-bigquery/.github/readme/synth.py.
On branch autosynth-readme
nothing to commit, working directory clean
2020-11-14 01:17:16,030 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/15cc9edc-80af-4477-a3a9-f60c98b52e91/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": "242082c06c1ef39fbf2229713e8816d7279e0d9d"
+        "sha": "fdfaaff2328e791a624fa2de4097dff39cd4950b"
       }
     },
     {

README.md

@@ -40,18 +40,18 @@ If you are using Maven without BOM, add this to your dependencies:
 <dependency>
   <groupId>com.google.cloud</groupId>
   <artifactId>google-cloud-bigquery</artifactId>
-  <version>1.124.5</version>
+  <version>1.124.6</version>
 </dependency>
 
 ```
 
 If you are using Gradle, add this to your dependencies
 ```Groovy
-compile 'com.google.cloud:google-cloud-bigquery:1.124.5'
+compile 'com.google.cloud:google-cloud-bigquery:1.124.6'
 ```
 If you are using SBT, add this to your dependencies
 ```Scala
-libraryDependencies += "com.google.cloud" % "google-cloud-bigquery" % "1.124.5"
+libraryDependencies += "com.google.cloud" % "google-cloud-bigquery" % "1.124.6"
 ```
 
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