Fix @VisibleForTesting given the newly deployed enforcement

Generated code is now also covered by @VisibleForTesting, including Dagger @Inject

This CL is a cleanup of auto-generated code by ghm@ from the Error Prone team

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=228748874

java/google/registry/model/poll/PollMessage.java

@@ -129,6 +129,14 @@ public abstract class PollMessage extends ImmutableObject
       super(instance);
     }
 
+    /**
+     * Manually set the ID for testing or in special circumstances.
+     *
+     * <p>In general the ID is auto-created, and there should be no need to set it manually.
+     *
+     * <p>This is only here for testing and for one special situation in which we're making a new
+     * poll message to replace an existing one, so it has to have the same ID.
+     */
     public B setId(Long id) {
       getInstance().id = id;
       return thisCastToDerived();