DO NOT MERGE: Testing release improvements

[bshaffer]

testing the release check in https://github.com/googleapis/google-cloud-php/pull/8725

• [x] test check fails with less than 2 yoshi approvers
• [x] test check increments the approver count as expected
• [x] test check triggers when approver count changes
• [x] test check triggers when PR description is changed
• [x] test check skips when M*JOR_VERSION_ALLOWED= does not exist in PR body
• [x] test check passes with M*JOR_VERSION_ALLOWED= and 2 yoshi approvers

The review triggered but the old failing review is still there

MAJOR_VERSION_ALLOWED=foo