Graceful Shutdown

[vwassan]

Part 1 of https://github.com/Shopify/semantic-query-engine/issues/428

• Add dev.yml
• Add dev lint, dev format and dev test commands
• Fix existing linting errors in the https://github.com/Shopify/psql-wire.
• Fix existing race conditions in tests in https://github.com/Shopify/psql-wire.
• Add graceful shutdown logic with timeout based on advice from this comment.
• Add relevant tests.

[crumley]

I think we should stick to the stdlib convention. See the docs for Close() vs Shutdown():

https://pkg.go.dev/net/http#Server.Close
https://pkg.go.dev/net/http#Server.Shutdown

Because Shutdown() accepts a ctx argument that allows the integrator to set the timeout. The way this code is structured there is no way to change it.