The re-generated tests in some PRs are in-complete. This is related to the keyword policy being added to reserved names list, thus requiring a rename of the use of policy in the library to something like policy_

PR#50 of grafeas : Failing tests
PR#51 of grafeas : Failing tests
PR#18 of python-binary-authorization : Failing tests
PR#112 of python-containeranalysis : Failing tests
PR#12 of python-artifact-registry : Failing tests

Also related: #835