chore: replace gcs-sdk-team with gcs-team (googleapis#15982)

b/478003109

Author: suztomo

.github/CODEOWNERS

@@ -6,7 +6,7 @@
 * @googleapis/cloud-sdk-cpp-team
 
 # These libraries are also owned by the GCS clients team.
-/google/cloud/storage/ @googleapis/gcs-sdk-team @googleapis/cloud-sdk-cpp-team
-/google/cloud/storagecontrol/ @googleapis/gcs-sdk-team @googleapis/cloud-sdk-cpp-team
-/google/cloud/storageinsights/ @googleapis/gcs-sdk-team @googleapis/cloud-sdk-cpp-team
-/google/cloud/storagetransfer/ @googleapis/gcs-sdk-team @googleapis/cloud-sdk-cpp-team
+/google/cloud/storage/ @googleapis/gcs-team @googleapis/cloud-sdk-cpp-team
+/google/cloud/storagecontrol/ @googleapis/gcs-team @googleapis/cloud-sdk-cpp-team
+/google/cloud/storageinsights/ @googleapis/gcs-team @googleapis/cloud-sdk-cpp-team
+/google/cloud/storagetransfer/ @googleapis/gcs-team @googleapis/cloud-sdk-cpp-team