Draft: Password modal to confirm two-factor actions

What does this MR do and why?

We created a new Vue component, TwoFactorAction, to replace ManageTwoFactorForm and to be used to destroy the one-time password authenticator.

The simpler TwoFactorAction component uses a better password field that toggle the visibility and takes less space because the password is inside the modal. By using the same modal in the whole page it makes the experience more consistent.

The new component is under the two_factor_actions feature flag.

On a follow-up, we will again re-use this new confirm modal to delete WebAuthn device.

MR acceptance checklist

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Screenshots or screen recordings

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State	Before	After
Close modal
Open modal

How to set up and validate locally

1. Enable the two_factor_actions (and optionally delete_otp_no_webauthn): /rails/features
2. Go to /-/profile/two_factor_auth
3. Create and destroy authenticators