faq: Add "Should I co-locate my repository?"

[jennings]

This sort of question comes up often in Discord, maybe it would be useful to have it in the FAQ?

Checklist

If applicable:

• [ ] I have updated CHANGELOG.md
• [ ] I have updated the documentation (README.md, docs/, demos/)
• [ ] I have updated the config schema (cli/src/config-schema.json)
• [ ] I have added tests to cover my changes

[ilyagr]

Thanks! I think we might also want to mention the confusing way Git tools interpret conflicted commits, #4428. WDYT?