Excavator: Render Bulldozer Bot config file (#44)

###### _excavator_ is a bot for automating changes across repositories.

Changes produced by the excavator/bulldozer-infra-oss check.

{runtimeCheckDesc}
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.bulldozer.yml

@@ -8,6 +8,7 @@ merge:
   options:
     squash:
       body: pull_request_body
+      message_delimiter: ==COMMIT_MSG==
   delete_after_merge: true
 update:
   whitelist: