Add captive prompts for the rest of MFA methods

[nikosdion]

Pull Request for comment #37912 (comment).

Ping @Kostelano @richard67

Summary of Changes

Adds captive login prompts for these MFA methods:

• Backup Codes
• TOTP (Authenticator Code)
• YubiKey

The rest of the methods already had it:

• Email
• Fixed
• WebAuthn

Testing Instructions

• Set up MFA using authentication code and YubiKey
• Note down your Backup Codes
• Log out and log back in

Actual result BEFORE applying this Pull Request

Choosing to validate with backup codes, TOTP or YubiKey would only display a text box without any help text to help you understand what to do.

Expected result AFTER applying this Pull Request

There is help text above the text box explaining how to obtain the code and proceed with the MFA.

Documentation Changes Required

None

Adds language strings

These three methods didn't have a captive prompt language string. I added three strings.

[richard67]

I have tested this item ✅ successfully on b5c7d4a

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[Kostelano]

I have tested this item ✅ successfully on b5c7d4a

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[richard67]

RTC

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[fancyFranci]

Thank you for the improvement!