docs(CONTRIBUTING.md): update installation steps

[qmg-drettie]

adds step to patch the compatibility suite in order for tests to pass

:airplane: Pre-flight checklist

• [x] I have read the Contributing Guidelines on pull requests.
• [x] If this is a code change: I have written unit tests and/or added dogfooding pages to fully verify the new behavior.
• [x] If this is a new API or substantial change: the PR has an accompanying issue (closes #0000) and the maintainers have approved on my working plan.

:memo: Summary

adds step to patch the compatibility suite in order for tests to pass

:rotating_light: Breaking Changes

:fire: Motivation

Cloned the repo for the first time and tried to run tests but some are failing. I found that the patch command is running within the github actions workflow to make the tests pass.

:hammer: Test Plan

:link: Related issues/PRs

[JP-Ellis]

Thanks! It was entirely an oversight on my part. The patch is temporary and will eventually be merged upstream; however, until such time, it is definitely better to make sure the docs are up to date!