[FrontOffice] Alternative to 2FA QR code

[ruslanbaidan]

Description
2FA is a must, but some operators using Monarc are not allowed to scan QR code for security reasons.
Therefore the current only option is to deactivate the 2 FA for them.
It would be important to have an alternative to the QR code to activate the 2FA.

Solution
Display the code, that is used to generate the QR code to be able to manually setup the 2FA account

[ruslanbaidan]

https://github.com/monarc-project/ng-client/tree/feature/505