Investigate support for FastAPI and FastAPI SQL Alchemy

[jrothrock]

From initial appearance, it looks like our Starlette integration works pretty well for FastAPI, but it doesn't appear that SQL timings are being collected when using the FastAPI SQL Alchemy library. Everything gets aggregated under 'View'

[adamchainz]

We don't collect any SQL timings in the async world. It's a bit harder and from what I recall the core agent and Python internals' data models aren't ready for parallel spans, something that's pretty much guaranteed with async apps.