chore: update owlbot.yaml (#347)

include v2beta

Author: eaball35

java-iam/.github/.OwlBot.yaml

@@ -29,3 +29,7 @@ deep-copy-regex:
   dest: "/owl-bot-staging/v1/grpc-google-iam-v1/src"
 - source: "/google/iam/v1/google-iam-v1-java/proto-google-iam-v1-java/src"
   dest: "/owl-bot-staging/v1/proto-google-iam-v1/src"
+- source: "/google/iam/v2beta/google-iam-v2beta-java/grpc-google-iam-v2beta-java/src"
+  dest: "/owl-bot-staging/v2beta/grpc-google-iam-v2beta/src"
+- source: "/google/iam/v2beta/google-iam-v2beta-java/proto-google-iam-v2beta-java/src"
+  dest: "/owl-bot-staging/v2beta/proto-google-iam-v2beta/src"