chore: regenerate README versions (#169)

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README.md

@@ -20,7 +20,7 @@ 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>7.0.0</version>
+      <version>8.0.0</version>
       <type>pom</type>
       <scope>import</scope>
     </dependency>

synth.metadata

@@ -11,7 +11,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-gameservices.git",
-        "sha": "51a450274d96fc125c51fd42870f7c9f5bcf7af8"
+        "sha": "de6a0a5ef750d0a4a278d31626462b50949e378a"
       }
     },
     {