cleanup: Fix mismatched region tags (GoogleCloudPlatform#3587)

Fixes #issue

> It's a good idea to open an issue first for discussion.

- [X] I have followed [Sample Format Guide](https://github.com/GoogleCloudPlatform/java-docs-samples/blob/master/SAMPLE_FORMAT.md)
- [ ] `pom.xml` parent set to latest `shared-configuration`
- [ ] Appropriate changes to README are included in PR
- [ ] API's need to be enabled to test (tell us)
- [ ] Environment Variables need to be set (ask us to set them)
- [ ] **Tests** pass:   `mvn clean verify` **required**
- [ ] **Lint**  passes: `mvn -P lint checkstyle:check` **required**
- [] **Static Analysis**:  `mvn -P lint clean compile pmd:cpd-check spotbugs:check` **advisory only**
- [X] Please **merge** this PR for me once it is approved.

Author: kurtisvg

functions/helloworld/hello-pubsub/src/test/java/functions/ExampleSystemTest.java

@@ -115,4 +115,4 @@ public void helloPubSub_shouldRunOnGcf() throws Exception {
     assertThat(logEntry).contains(name);
   }
 }
-// [END functions_pubsub_integration_test]
+// [END functions_pubsub_system_test]

functions/helloworld/kotlin-hello-pubsub/src/main/kotlin/functions/eventpojos/PubSubMessage.kt

@@ -16,7 +16,7 @@
 
 package functions.eventpojos
 
-// [END functions_helloworld_pubsub_message]
+// [START functions_helloworld_pubsub_message]
 class PubSubMessage {
     // Cloud Functions uses GSON to populate this object.
     // Field types/names are specified by Cloud Functions

functions/helloworld/scala-hello-pubsub/src/main/scala/functions/eventpojos/PubSubMessage.scala

@@ -34,6 +34,6 @@ class PubSubMessage { // Cloud Functions uses GSON to populate this object.
   def setData(data: String): Unit = {
     this.data = data : String;
   }
-  // [END functions_helloworld_pubsub_message]
+  // [START functions_helloworld_pubsub_message]
 }
 // [END functions_helloworld_pubsub_message]

iot/api-client/codelab/manager/src/main/java/com/example/cloud/iot/examples/MqttCommandsDemo.java

@@ -76,7 +76,6 @@ private static String createJwtRsa(String projectId, String privateKeyFile)
 
     return jwtBuilder.signWith(SignatureAlgorithm.RS256, kf.generatePrivate(spec)).compact();
   }
-  // [END iot_mqtt_jwt]
 
   /** Create a Cloud IoT Core JWT for the given project id, signed with the given ES key. */
   private static String createJwtEs(String projectId, String privateKeyFile)
@@ -243,7 +242,6 @@ public static void mqttDeviceDemo(
       throw new IllegalArgumentException(
           "Invalid algorithm " + algorithm + ". Should be one of 'RS256' or 'ES256'.");
     }
-    // [END iot_mqtt_configuremqtt]
 
     // [START iot_mqtt_publish]
     // Create a client, and connect to the Google MQTT bridge.

iot/api-client/manager/src/main/java/com/example/cloud/iot/examples/MqttExample.java

@@ -360,7 +360,6 @@ protected static void mqttDeviceDemo(MqttExampleOptions options)
       throw new IllegalArgumentException(
           "Invalid algorithm " + options.algorithm + ". Should be one of 'RS256' or 'ES256'.");
     }
-    // [END iot_mqtt_configuremqtt]
 
     // [START iot_mqtt_publish]
     // Create a client, and connect to the Google MQTT bridge.

jobs/v3/src/main/java/com/google/samples/AutoCompleteSample.java

@@ -59,8 +59,9 @@ public static void jobTitleAutoComplete(String companyName, String query) throws
 
     System.out.println(results);
   }
-  // [END auto_complete_default]
+  // [END auto_complete_job_title]
 
+  // [START auto_complete_default]
   /** Auto completes job titles within given companyName. */
   public static void defaultAutoComplete(String companyName, String query) throws IOException {
     Complete complete =

jobs/v3/src/main/java/com/google/samples/BasicJobSample.java

@@ -123,7 +123,7 @@ public static Job updateJob(String jobName, Job jobToBeUpdated) throws IOExcepti
     }
   }
 
-  //
+  // [END update_job]
 
   // [START update_job_with_field_mask]
 

spanner/cloud-client/src/main/java/com/example/spanner/SpannerSample.java

@@ -2113,6 +2113,7 @@ public static void main(String[] args) throws Exception {
       // Use client here...
       // [END init_client]
       run(dbClient, dbAdminClient, instanceAdminClient, command, db, backup);
+      // [START init_client]
     } finally {
       spanner.close();
     }

spanner/spring-data/src/main/java/com/example/spanner/SpannerTemplateSample.java

@@ -28,7 +28,6 @@
  * A quick start code for Spring Data Cloud Spanner. It demonstrates how to use SpannerTemplate to
  * execute DML and SQL queries, save POJOs, and read entities.
  */
-// [START spring_data_spanner_template_sample]
 @Component
 public class SpannerTemplateSample {
 

vision/cloud-client/src/main/java/com/example/vision/snippets/DetectWebEntities.java

@@ -16,8 +16,6 @@
 
 package com.example.vision.snippets;
 
-// [START vision_web_detection]
-
 import com.google.cloud.vision.v1.AnnotateImageRequest;
 import com.google.cloud.vision.v1.BatchAnnotateImagesResponse;
 import com.google.cloud.vision.v1.Feature;