chore: fix ignore regex in owlbot.yaml (#2671)

* chore: fix ignore regex in owlbot.yaml

* re-add samples to owlbot.py

* fix regex format

Author: ddelgrosso1

.github/.OwlBot.yaml

@@ -15,8 +15,7 @@ docker:
   image: gcr.io/cloud-devrel-public-resources/owlbot-nodejs:latest
 
 deep-preserve-regex:
-  - /\.kokoro/samples-test\.sh
+  - /.kokoro/samples-test.sh
 
 
 begin-after-commit-hash: 674a41e0de2869f44f45eb7b1a605852a5394bba
-