feat: remove beam I/O from repo and redirect to beam (#479)

Author: dpcollins-google

pom.xml

@@ -121,7 +121,6 @@
  <module>google-cloud-pubsublite</module>
  <module>grpc-google-cloud-pubsublite-v1</module>
  <module>proto-google-cloud-pubsublite-v1</module>
- <module>pubsublite-beam-io</module>
  </modules>
 
  <profiles>

pubsublite-beam-io/EnableAutoValue.txt

@@ -3,17 +3,18 @@
 1. Add the following to your POM file to download the Pub/Sub Lite I/O.
 ```xml
 <dependency>
- <groupId>com.google.cloud</groupId>
- <artifactId>pubsublite-beam-io</artifactId>
- <version>0.6.0</version>
+  <groupId>org.apache.beam</groupId>
+  <artifactId>beam-sdks-java-io-google-cloud-platform</artifactId>
+  <version>2.27.0</version>
 </dependency>
 ```
 1. Create a topic using `gcloud pubsub lite-topics create`
 1. Write some messages using:
 
  ```java
- import com.google.cloud.pubsublite.beam.PubsubLiteIO;
- import com.google.cloud.pubsublite.beam.PublisherOptions;
+ import org.apache.beam.sdk.io.gcp.pubsublite.PubsubLiteIO;
+ import org.apache.beam.sdk.io.gcp.pubsublite.PublisherOptions;
+ import com.google.cloud.pubsublite.proto.PubSubMessage;
  import com.google.cloud.pubsublite.*;
 
  ...
@@ -23,7 +24,7 @@
 
  ...
 
- PCollection<Message> messages = ...;
+ PCollection<PubSubMessage> messages = ...;
  messages.apply("Write messages", PubsubLiteIO.write(
  PublisherOptions.newBuilder()
  .setTopicPath(TopicPath.newBuilder()
@@ -39,6 +40,7 @@
  ```java
  import com.google.cloud.pubsublite.beam.PubsubLiteIO;
  import com.google.cloud.pubsublite.beam.SubscriberOptions;
+ import com.google.cloud.pubsublite.proto.SequencedMessage;
  import com.google.cloud.pubsublite.*;
  import com.google.cloud.pubsublite.cloudpubsub.FlowControlSettings;