[REQUIRED] Environment info

firebase-tools: 8.16.2 (latest)

Platform: macOS

[REQUIRED] Test case

Literally anywhere, but sure you can use this: https://github.com/kentcdodds/elaborate

[REQUIRED] Steps to reproduce

1. Run firebase emulators:start
2. Notice there's a ton of output, much of it is not useful
3. Dig through the firebase-tools code and find this handy option
4. Try to enable it with firebase emulators:start --quiet
5. Notice the error: unknown option '--quiet' output
6. Try adding the option here
7. Run firebase emulators:start --quiet again
8. Notice that you no longer get the error, but this.args.quiet is still undefined in functionsEmulator.js so that doesn't work either.
9. Discover emulators-startts and try a few things but ultimately give up.

[REQUIRED] Expected behavior

I want to be able to silence most of the output when I start my firebase function.

[REQUIRED] Actual behavior

Instead, I get a bunch of output that hides output from my functions:

Can you find my own logs? After a bit of time looking for them, so can I:

>  getting post with ID xbxfZqu5gXN5QyhcfmGk

I'd much rather not have to search through all that output, which is why I'd like to have this --quiet option. Or perhaps a --loglevel option or something. I just need a way to silence the firebase logs.