add missing dependency

Author: nbayati

cab-token-generator/pom.xml

@@ -31,6 +31,11 @@
       <groupId>com.google.http-client</groupId>
       <artifactId>google-http-client</artifactId>
     </dependency>
+    <dependency>
+      <groupId>com.google.http-client</groupId>
+      <artifactId>google-http-client-gson</artifactId>
+      <scope>test</scope>
+    </dependency>
     <dependency>
       <groupId>com.google.errorprone</groupId>
       <artifactId>error_prone_annotations</artifactId>