docs(CONTRIBUTING.md): update installation steps

[qmg-drettie]

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

✈️ Pre-flight checklist

• I have read the Contributing Guidelines on pull requests.
• If this is a code change: I have written unit tests and/or added dogfooding pages to fully verify the new behavior.
• 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.

📝 Summary

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

🚨 Breaking Changes

🔥 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.

🔨 Test Plan

🔗 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!