chore: regenerate README (#651)

This PR was generated using Autosynth. 🌈


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

```
2021-08-27 15:06:44,854 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-vision/.github/readme/synth.py.
On branch autosynth-readme
nothing to commit, working tree clean
2021-08-27 15:06:46,457 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/42d20069-e916-4cc6-b6d3-a319ea59e98c/targets

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

@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-vision.git",
-        "sha": "22e32507994c55001301708bb6acb0503def04fd"
+        "sha": "d557635d841ea0aedfef3c1f3a35e202406671e0"
       }
     },
     {

README.md

@@ -19,7 +19,7 @@ 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>21.0.0</version>
+      <version>22.0.0</version>
       <type>pom</type>
       <scope>import</scope>
     </dependency>
@@ -50,7 +50,7 @@ If you are using Maven without BOM, add this to your dependencies:
 If you are using Gradle 5.x or later, add this to your dependencies
 
 ```Groovy
-implementation platform('com.google.cloud:libraries-bom:21.0.0')
+implementation platform('com.google.cloud:libraries-bom:22.0.0')
 
 compile 'com.google.cloud:google-cloud-vision'
 ```