chore: regenerate README (#889)

This PR was generated using Autosynth. 🌈


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

```
2020-10-29 19:52:31,453 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-bigquery/.github/readme/synth.py.
On branch autosynth-readme
nothing to commit, working directory clean
2020-10-29 19:52:32,470 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/9a152f72-b02d-4a15-9583-9f6b2d36c07d/targets

- [ ] To automatically regenerate this PR, check this box.

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

@@ -4,14 +4,14 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-bigquery.git",
-        "sha": "b031447d691de51678a0654c27b0f621672dd52a"
+        "sha": "a9e45f83c0344886037939a04333194de1413bfc"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "fd3584b01cedd6c9f79d08be4e2365085f955aa5"
+        "sha": "ea52b8a0bd560f72f376efcf45197fb7c8869120"
       }
     }
   ]

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>1.123.2</version>
+  <version>1.124.0</version>
 </dependency>
 
 ```
 
 If you are using Gradle, add this to your dependencies
 ```Groovy
-compile 'com.google.cloud:google-cloud-bigquery:1.123.2'
+compile 'com.google.cloud:google-cloud-bigquery:1.124.0'
 ```
 If you are using SBT, add this to your dependencies
 ```Scala
-libraryDependencies += "com.google.cloud" % "google-cloud-bigquery" % "1.123.2"
+libraryDependencies += "com.google.cloud" % "google-cloud-bigquery" % "1.124.0"
 ```
 
 ## Authentication