chore: add common pull request template (#9422)
chore: add common pull request template (#9422)


GoogleCloudPlatform/gcloud-python,tswast/google-cloud-python,tswast/google-cloud-python,tseaver/google-cloud-python,tseaver/google-cloud-python,tseaver/google-cloud-python,GoogleCloudPlatform/gcloud-python,googleapis/google-cloud-python,tswast/google-cloud-python,googleapis/google-cloud-python