chore: regenerate README (#1265)

This PR was generated using Autosynth. 🌈


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

```
2021-08-24 20:22:18,909 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-bigquerystorage/.github/readme/synth.py.
On branch autosynth-readme
nothing to commit, working tree clean
2021-08-24 20:22:20,009 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/ab19ca22-b9f1-4d70-9c1a-427d90f84573/targets

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

@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-bigquerystorage.git",
-        "sha": "129c6ffa94e59cd38608283b4014e9c210f2f95c"
+        "sha": "6e42fa024eac95fc43676ff1d37dd71c89824376"
       }
     },
     {

README.md

@@ -41,7 +41,7 @@ If you are using Maven without BOM, add this to your dependencies:
 <dependency>
   <groupId>com.google.cloud</groupId>
   <artifactId>google-cloud-bigquerystorage</artifactId>
-  <version>2.0.4</version>
+  <version>2.1.0</version>
 </dependency>
 
 ```
@@ -56,13 +56,13 @@ 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:2.0.4'
+compile 'com.google.cloud:google-cloud-bigquerystorage:2.1.0'
 ```
 
 If you are using SBT, add this to your dependencies
 
 ```Scala
-libraryDependencies += "com.google.cloud" % "google-cloud-bigquerystorage" % "2.0.4"
+libraryDependencies += "com.google.cloud" % "google-cloud-bigquerystorage" % "2.1.0"
 ```
 
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