docs(run): update region tag (GoogleCloudPlatform#1216)

Author: averikitsch

run/helloworld/Dockerfile

@@ -5,13 +5,14 @@
 # You may obtain a copy of the License at
 #
 #    https://www.apache.org/licenses/LICENSE-2.0
-# 
+#
 # Unless required by applicable law or agreed to in writing, software
 # distributed under the License is distributed on an "AS IS" BASIS,
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# [START cloudrun_helloworld_dockerfile]
 # [START run_helloworld_dockerfile]
 
 # Use the official PHP image.
@@ -51,3 +52,4 @@ RUN sed -i 's/80/${PORT}/g' /etc/apache2/sites-available/000-default.conf /etc/a
 RUN mv "$PHP_INI_DIR/php.ini-development" "$PHP_INI_DIR/php.ini"
 
 # [END run_helloworld_dockerfile]
+# [END cloudrun_helloworld_dockerfile]

run/helloworld/index.php

@@ -15,9 +15,11 @@
  * limitations under the License.
  */
 
+// [START cloudrun_helloworld_service]
 // [START run_helloworld_service]
 
 $name = getenv('NAME', true) ?: 'World';
 echo sprintf('Hello %s!', $name);
 
 // [END run_helloworld_service]
+// [END cloudrun_helloworld_service]