chore: relocate owl bot post processor

.github/.OwlBot.yaml

diff --git a/.github/.OwlBot.yaml b/.github/.OwlBot.yaml
index 892fbc2..ed6155a 100644
--- a/.github/.OwlBot.yaml
+++ b/.github/.OwlBot.yaml
@@ -13,6 +13,6 @@
 # limitations under the License.
 
 docker:
-  image: gcr.io/repo-automation-bots/owlbot-python:latest
+  image: gcr.io/cloud-devrel-public-resources/owlbot-python:latest
 
 begin-after-commit-hash: ee56c3493ec6aeb237ff515ecea949710944a20f