chore: update pom

Author: blakeli0

java-showcase/gapic-showcase/pom.xml

@@ -102,10 +102,6 @@
       <groupId>com.google.api.grpc</groupId>
       <artifactId>proto-google-common-protos</artifactId>
     </dependency>
-    <dependency>
-      <groupId>com.google.api.grpc</groupId>
-      <artifactId>proto-gapic-showcase-v1beta1-3.25.8</artifactId>
-    </dependency>
     <dependency>
       <groupId>com.google.api.grpc</groupId>
       <artifactId>grpc-google-common-protos</artifactId>