chore: add debug logs around shutdownCh

[jackwotherspoon]

Add additional debug log entries around shutdownCh to allow for verification that SIGINT/SIGTERM signals are being properly sent.

[jackwotherspoon]

@enocom feel free to leave suggestions for additional spots I could add debug log entries and I'll happily add them 😄

[enocom]

There are a few other spots. Just adding a logging message directly above these lines will be good enough I think.

cloud-sql-proxy/cmd/root.go

Line 1026 in b4076f3

shutdownCh <- fmt.Errorf("unable to start: %v", err)

cloud-sql-proxy/cmd/root.go

Line 1130 in b4076f3

go func() { shutdownCh <- p.Serve(ctx, notify) }()

cloud-sql-proxy/cmd/root.go

Line 1156 in b4076f3

case shutdownCh <- errQuitQuitQuit:

cloud-sql-proxy/cmd/root.go

Line 1177 in b4076f3

shutdownCh <- fmt.Errorf("failed to start HTTP server: %v", err)

[jackwotherspoon]

There are a few other spots. Just adding a logging message directly above these lines will be good enough I think.

cloud-sql-proxy/cmd/root.go

Line 1026 in b4076f3

shutdownCh <- fmt.Errorf("unable to start: %v", err)

cloud-sql-proxy/cmd/root.go

Line 1130 in b4076f3

go func() { shutdownCh <- p.Serve(ctx, notify) }()

cloud-sql-proxy/cmd/root.go

Line 1156 in b4076f3

case shutdownCh <- errQuitQuitQuit:

cloud-sql-proxy/cmd/root.go

Line 1177 in b4076f3

shutdownCh <- fmt.Errorf("failed to start HTTP server: %v", err)

The last two don't have access to the logger so I couldn't add them...