Very slow startup and cloud function updates if working without internet connection

### Environment info

**firebase-tools:**
11.0.0

**Platform:**
OS: Pop!_OS 22.04 LTS x86_64
### Test case

start emulator without internet connection

### Steps to reproduce

Run: 'firebase --debug emulators:start' or update a cloud function

### Expected behavior

start emulator and update cloud functions in a couple of seconds (like when running with internet connection)

### Actual behavior

The emulator stops **more than a minute** showing the message:
Validating nodejs source

The same happens when updating a function

Reproduce the issue offline with `firebase --debug emulators:start` and by updating a cloud function, then capture where execution remains at “Validating nodejs source.” Trace that validation entry point and compare behavior with and without internet access. Done means emulator startup and cloud function updates complete in a couple of seconds offline, as they do online.

Written by the indexing model from the issue text.