fix(deps): update dependency com.google.cloud:google-cloud-shared-dependencies to v2.8.0 (#959)

Author: renovate-bot

gapic-generator-java/pom.xml

@@ -15,7 +15,7 @@
       <dependency>
         <groupId>com.google.cloud</groupId>
         <artifactId>google-cloud-shared-dependencies</artifactId>
-        <version>2.7.0</version>
+        <version>2.8.0</version>
         <type>pom</type>
         <scope>import</scope>
       </dependency>