Release Firestore Emulator v1.19.4

[harshyyy21]

Description

This PR updates the Firestore Emulator to v1.19.4.

Scenarios Tested

 node lib/bin/firebase.js emulators:start --only firestore
(node:55562) [DEP0040] DeprecationWarning: The `punycode` module is deprecated. Please use a userland alternative instead.
(Use `node --trace-deprecation ...` to show where the warning was created)
⚠  Could not find config (firebase.json) so using defaults.
i  emulators: Starting emulators: firestore
⚠  firestore: Did not find a Cloud Firestore rules file specified in a firebase.json config file.
⚠  firestore: The emulator will default to allowing all reads and writes. Learn more about this option: https://firebase.google.com/docs/emulator-suite/install_and_configure#security_rules_configuration.
i  firestore: downloading cloud-firestore-emulator-v1.19.4.jar...
Progress: =======================================================================================================================> (100% of 66MB
i  firestore: Removing outdated emulator files: cloud-firestore-emulator-v1.19.3.jar
i  firestore: Firestore Emulator logging to firestore-debug.log
✔  firestore: Firestore Emulator UI websocket is running on 9150.
⚠  emulators: The Emulator UI is not starting, either because none of the running emulators have a UI component or the Emulator UI cannot determine the Project ID. Pass the --project flag to specify a project.