Remove gRPC and protos from @firebase/testing

[samtstern]

Removes the protos and @grpc/grpc-js from @firebase/testing and replaces it with simple REST calls.

Also fun fact: this module never actually listed grpc-js as a dependency so we were just lucky.

[google-oss-bot]

Binary Size Report

Affected SDKs

• @firebase/testing

  Type	Base (246ed9d)	Head (791fcbe)	Diff
  main	6.67 kB	6.34 kB	-331 B (-5.0%)

Test Logs

• Base (246ed9d6): https://github.com/firebase/firebase-js-sdk/actions/runs/141079705
• Head (791fcbe1): https://github.com/firebase/firebase-js-sdk/actions/runs/141118969

[samtstern]

@firebase/messaging: npm ERR! code ELIFECYCLE
@firebase/messaging: npm ERR! errno 1
@firebase/messaging: npm ERR! [email protected] test: `mocha --exit`
@firebase/messaging: npm ERR! Exit status 1
@firebase/messaging: npm ERR! 
@firebase/messaging: npm ERR! Failed at the [email protected] test script.
@firebase/messaging: npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
@firebase/messaging: npm ERR! A complete log of this run can be found in:
@firebase/messaging: npm ERR!     /home/runner/.npm/_logs/2020-06-19T17_43_30_344Z-debug.log

These keep getting in my way.

[yuchenshi]

Please keep trying -- I doubt it's related. It might be just flaky tests. If this keep happening let's pull in some folks who might be familiar with it.