(GHA) Optimize when code checks in CI are executed in PRs

[theodur]

Description

Currently, our CI workflow runs code checks on all PRs. There are a few instances where code checks don't need to be run on a PR, e.g. when a PR includes only changes to Markdown files. We can optimize the [Code Quality] Code Checks workflow to only run when PRs include relevant code changes.

Acceptance criteria

• Determine which scenarios code checks don't need to run
• Update the Code Checks workflow to not run in those scenarios

[timwright12]

Kicking this over the the release team (cc: @bischoffa )

[bischoffa]

Given its coming to Qart - assigned to Charnelle, adding to DevOps Q3 epic, moved to new issues so it can be groomed and reviewed prior to being worked