Add support for b2clogin hostnames

[rnrneverdies]

MSFT Recommends to use b2clogin.com hostnames for B2C applications instead of login.microsoftonline.com.

And given that MSAL.js is unable to validate b2clogin authority. This fix detects if the instance points to b2clogin.com page and set the validateAuthority to false accordingly.

Reference: https://docs.microsoft.com/en-us/azure/active-directory-b2c/b2clogin https://docs.microsoft.com/en-us/azure/active-directory/develop/msal-b2c-overview

[DsEsteban]

Hi!!

This solution helped me to solve the problem! It would be great if it could be merged to the project! Any help i could provide for that? :D

[rnrneverdies]

Closing