chore: regenerate README (#696)

This PR was generated using Autosynth. 🌈


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

```
2021-05-13 15:56:15,012 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-automl/.github/readme/synth.py.
On branch autosynth-readme
nothing to commit, working tree clean
2021-05-13 15:56:16,711 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/80fc46b5-afd0-4bcb-a898-cb07e0c78de7/targets

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

@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-automl.git",
-        "sha": "f6b156d79d75f175c1521032e0c289137f8f2978"
+        "sha": "bdc3fb1a93e90db844da9e291f085acf2069a0d2"
       }
     },
     {

README.md

@@ -52,7 +52,7 @@ If you are using Maven without BOM, add this to your dependencies:
 <dependency>
   <groupId>com.google.cloud</groupId>
   <artifactId>google-cloud-bigquery</artifactId>
-  <version>1.128.1</version>
+  <version>1.129.0</version>
 </dependency>
 <dependency>
   <groupId>com.google.cloud</groupId>