chore: Remove explictly declared grpc-gcp version (#7374)

Author: blakeli0

libraries-bom/pom.xml

@@ -79,11 +79,6 @@
         <type>pom</type>
         <scope>import</scope>
       </dependency>
-      <dependency>
-        <groupId>com.google.cloud</groupId>
-        <artifactId>grpc-gcp</artifactId>
-        <version>1.9.0</version>
-      </dependency>
     </dependencies>
   </dependencyManagement>