Support specifying database in FirestoreV1ReadFn (resolves #36904)

CHANGES.md

@@ -72,7 +72,7 @@
 
 ## New Features / Improvements
 
-* X feature added (Java/Python) ([#X](https://github.com/apache/beam/issues/X)).
+* Support configuring Firestore database on ReadFn transforms (Java) ([#36904](https://github.com/apache/beam/issues/36904)).
 
 ## Breaking Changes
 

sdks/java/io/google-cloud-platform/src/main/java/org/apache/beam/sdk/io/gcp/firestore/FirestoreStatefulComponentFactory.java

@@ -63,12 +63,10 @@ private FirestoreStatefulComponentFactory() {}
    * <p>The instance returned by this method is expected to bind to the lifecycle of a bundle.
    *
    * @param options The instance of options to read from
+   * @param configuredProjectId The project to target, if null, falls back to value in options.
+   * @param configuredDatabaseId The database to target, if null, falls back to value in options.
    * @return a new {@link FirestoreStub} pre-configured with values from the provided options
    */
-  FirestoreStub getFirestoreStub(PipelineOptions options) {
-    return getFirestoreStub(options, null, null);
-  }
-
   FirestoreStub getFirestoreStub(
       PipelineOptions options,
       @Nullable String configuredProjectId,