Re-enable firestore integration tests (revert #27267) (#27743)

* Re-enable firestore integration tests (revert #27267)

* Also restore in direct runner test suite

runners/google-cloud-dataflow-java/build.gradle

@@ -566,8 +566,6 @@ task googleCloudPlatformLegacyWorkerIntegrationTest(type: Test, dependsOn: copyG
   exclude '**/PubsubReadIT.class'
   exclude '**/FhirIOReadIT.class'
   exclude '**/gcp/spanner/changestreams/it/*.class'
-  // TODO(https://github.com/apache/beam/issues/25851) failing due to internal Firestore breaking change
-  exclude '**/FirestoreV1IT.class'
   maxParallelForks 4
   classpath = configurations.googleCloudPlatformIntegrationTest
   testClassesDirs = files(project(":sdks:java:io:google-cloud-platform").sourceSets.test.output.classesDirs)
@@ -616,8 +614,6 @@ task googleCloudPlatformRunnerV2IntegrationTest(type: Test) {
   exclude '**/FhirIOLROIT.class'
   exclude '**/FhirIOSearchIT.class'
   exclude '**/FhirIOPatientEverythingIT.class'
-  // TODO(https://github.com/apache/beam/issues/25851) failing due to internal Firestore breaking change
-  exclude '**/FirestoreV1IT.class'
 
   maxParallelForks 4
   classpath = configurations.googleCloudPlatformIntegrationTest