feat(firebase_ui_auth): Use icon from OAuth provider as a fallback in ProfileScreen

[Rexios80]

Description

In the ProfileScreen, use the OAuth provider icon as a fallback if available

Replaces #451

Related Issues

closes #383

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[Rexios80]

@russellwheatley any comments on this?

[github-actions]

Hello 👋, this PR has been opened for more than 2 months with no activity on it.

If you think this is a mistake please comment and ping a maintainer to get this merged ASAP! Thanks for contributing!

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[Rexios80]

@russellwheatley any thoughts?