fix unused depedenecy declaration issue

Author: sakthivelmanii

google-cloud-spanner-executor/pom.xml

@@ -265,7 +265,7 @@
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-dependency-plugin</artifactId>
           <configuration>
-            <ignoredDependencies> com.google.api:gax</ignoredDependencies>
+            <ignoredDependencies> com.google.api:gax,org.apache.maven.surefire:surefire-junit4 </ignoredDependencies>
           </configuration>
         </plugin>
       </plugins>