chore: regenerate README (#950)

This PR was generated using Autosynth. 🌈


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

```
2021-03-18 22:45:20,095 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-bigquerystorage/.github/readme/synth.py.
On branch autosynth-readme
nothing to commit, working tree clean
2021-03-18 22:45:21,018 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/93099bcc-ab35-48d5-ab7a-79fbfbcb0bba/targets

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

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

@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-bigquerystorage.git",
-        "sha": "1554247cf55aa56281a530c721ab1650699a3efc"
+        "sha": "3835c8083b912a13d4ff4d7d08adca5e98c6ae99"
       }
     },
     {

README.md

@@ -17,7 +17,7 @@ If you are using Maven with [BOM][libraries-bom], add this to your pom.xml file
     <dependency>
       <groupId>com.google.cloud</groupId>
       <artifactId>libraries-bom</artifactId>
-      <version>19.1.0</version>
+      <version>19.2.0</version>
       <type>pom</type>
       <scope>import</scope>
     </dependency>
@@ -38,25 +38,25 @@ If you are using Maven without BOM, add this to your dependencies:
 <dependency>
   <groupId>com.google.cloud</groupId>
   <artifactId>google-cloud-bigquerystorage</artifactId>
-  <version>1.15.0</version>
+  <version>1.15.1</version>
 </dependency>
 
 ```
 
 If you are using Gradle 5.x or later, add this to your dependencies
 ```Groovy
-implementation platform('com.google.cloud:libraries-bom:19.1.0')
+implementation platform('com.google.cloud:libraries-bom:19.2.0')
 
 compile 'com.google.cloud:google-cloud-bigquerystorage'
 ```
 If you are using Gradle without BOM, add this to your dependencies
 ```Groovy
-compile 'com.google.cloud:google-cloud-bigquerystorage:1.15.0'
+compile 'com.google.cloud:google-cloud-bigquerystorage:1.15.1'
 ```
 
 If you are using SBT, add this to your dependencies
 ```Scala
-libraryDependencies += "com.google.cloud" % "google-cloud-bigquerystorage" % "1.15.0"
+libraryDependencies += "com.google.cloud" % "google-cloud-bigquerystorage" % "1.15.1"
 ```
 
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