fix(firebase_ui_auth): Avoid redundant confirmation on account deletion

[EArminjon]

Description

When user try to delete his account, when the exception 'requires-recent-login' appear, user need to login again and click again on the modal to confirm the account deletion. That's redundant.

Related Issues

This PR can also bring some beneficts to this PR : #493, if developer override the deletion modal to provide one (for example) using a TextController to ensure that user well want to delete his account (no miss click), the recall of the confirmation will present twice a TextController to fill.

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