Pubsub : Cleanup dependency (#5667)

* cleanup unused dependency of contrib-google-cloud-pubsub

* remove unused dependency of pubsub

* add the newline at the end of the file

Author: athakor

google-cloud-clients/google-cloud-pubsub/pom.xml

@@ -18,10 +18,6 @@
     <site.installationModule>google-cloud-pubsub</site.installationModule>
   </properties>
   <dependencies>
-    <dependency>
-      <groupId>${project.groupId}</groupId>
-      <artifactId>google-cloud-core</artifactId>
-    </dependency>
     <dependency>
       <groupId>${project.groupId}</groupId>
       <artifactId>google-cloud-core-grpc</artifactId>
@@ -34,18 +30,6 @@
       <groupId>com.google.api.grpc</groupId>
       <artifactId>grpc-google-cloud-pubsub-v1</artifactId>
     </dependency>
-    <dependency>
-      <groupId>io.grpc</groupId>
-      <artifactId>grpc-netty-shaded</artifactId>
-    </dependency>
-    <dependency>
-      <groupId>io.grpc</groupId>
-      <artifactId>grpc-stub</artifactId>
-    </dependency>
-    <dependency>
-      <groupId>io.grpc</groupId>
-      <artifactId>grpc-auth</artifactId>
-    </dependency>
     <dependency>
       <groupId>com.google.auto.value</groupId>
       <artifactId>auto-value</artifactId>