feat: add git to topo health checks

[federicobozzini]

Changes

• what title says

Checklist

• 🤖 This change is covered by tests as required.
• 🤹 All required manual testing has been performed.
• 📖 All documentation updates are complete.

[th3james]

I wonder if this is getting a bit excessive and we're creating a big scary checklist with relatively poor signal-to-noise ratio. If we are going to do this is should be SeverityWarning because it's only necessary for topo clone with git, we still support dir:

[federicobozzini]

Very reasonable 2088ba7

[muchzill4]

I'd rather we didn't do this (just yet).

topo health right now is tightly integrated into deployment flow. Heck, even topo deploy tells you to run topo health if the deployment fails. Reporting git status might be confusing unless we somehow group the software health checks into respective flow groups (clone, deploy). I believe we should think more carefully before bolting on another check.

big scary checklist with relatively poor signal-to-noise ratio

Sums it up pretty nicely.

My preference would be to scope this change to README.md for now.