chore(bigtable): Revert bigtable-admin to gapic v1
chore(bigtable): Revert bigtable-admin to gapic v1


dazuma/google-cloud-ruby,googleapis/google-cloud-ruby,googleapis/google-cloud-ruby,googleapis/google-cloud-ruby,dazuma/google-cloud-ruby,dazuma/google-cloud-ruby,dazuma/google-cloud-ruby,dazuma/google-cloud-ruby,dazuma/google-cloud-ruby,googleapis/google-cloud-ruby,googleapis/google-cloud-ruby,googleapis/google-cloud-ruby