All Submissions:

• Does your code follow the P75Izm-1JH-p2 standards?
• Have you written new tests for your changes, as applicable?
• Have you successfully run tests with your changes locally?

Changes proposed in this Pull Request:

Closes QAO-40
Contributes to QAO-23

Pins Github actions to full commit SHAs as immutable references.
Skipped all official GitHub actions.
No version update for setup-php action - used the latest commit in the tag that was already used.
Bumped one of the usages of actions/cache from v1 to v4 to fix the workflow that was failing because v1 is deprecated.
Removes dcarbone/install-jq-action action - the ubuntu runner image already comes with jq preinstalled

How to test the changes in this Pull Request:

PHP unit tests workflow should pass in CI

Other information:

• Have you checked to ensure there aren't other open Pull Requests for the same update/change?

Changelog entry

CI workflow updates