Update firebase to version 4.0.0 🚀

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Hello lovely humans,

firebase just published its new version 4.0.0.

State	Update 🚀
Dependency	firebase
New version	4.0.0
Type	dependency

This version is not covered by your current version range.

Without accepting this pull request your project will work just like it did before. There might be a bunch of new features, fixes and perf improvements that the maintainers worked on for you though.

I recommend you look into these changes and try to get onto the latest version of firebase.
Given that you have a decent test suite, a passing build is a strong indicator that you can take advantage of these changes by merging the proposed change into your project. Otherwise this branch is a great starting point for you to work on the update.

Do you have any ideas how I could improve these pull requests? Did I report anything you think isn’t right?
Are you unsure about how things are supposed to work?

There is a collection of frequently asked questions and while I’m just a bot, there is a group of people who are happy to teach me new things. Let them know.

Good luck with your project ✨

You rock!

🌴

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GitHub Release

Features

• Added support for phone number authentication using the following APIs:
  • PhoneAuthProvider
  • firebase.auth.Auth.prototype.signInWithPhoneNumber
  • firebase.User.prototype.linkWithPhoneNumber
  • firebase.User.prototype.reauthenticateWithPhoneNumber
• Augmented the IdP data (for a list of all supported fields see firebase.auth.UserCredential) returned by the following APIs:
  • firebase.auth.Auth.prototype.signInAndRetrieveDataWithCredential
  • firebase.User.prototype.linkAndRetrieveDataWithCredential
  • firebase.User.prototype.reauthenticateAndRetrieveDataWithCredential
• Added the firebase.auth.Auth.prototype.onIdTokenChanged method that triggers on ID token changes.

Breaking Changes

• firebase.auth.Auth.prototype.onAuthStateChanged now triggers on sign in and sign out.
• firebase.User.prototype.reauthenticate has been removed in favor of firebase.User.prototype.reauthenticateWithCredential.
• firebase.User.prototype.link has been removed in favor of firebase.User.prototype.linkWithCredential.
• firebase.AuthCredential.prototype.provider has been removed in favor of firebase.AuthCredential.prototype.providerId.

Deprecations

• Removed support for deprecated serviceAccount and credential properties from the Node.js SDK. If you were previously using the Firebase Javascript SDK to use these properties, use the Firebase Admin Node.js SDK instead.
• Deprecated firebase.User.prototype.getToken in favor of firebase.User.prototype.getIdToken.

Fixes

• Fixed an issue where firebase.User.prototype.updateProfile was not triggering an update in password provider data.

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This change is