Fix GraphQL controller redirect when 2fa is required

What does this MR do and why?

Fixes the GraphQL controller redirecting when 2fa is required for a user. This was causing errors when the attention request was enabled because the GraphQL request in the header would trigger a new 2fa secret causing the 2fa form to error out.

This change makes it so the GraphQL controller returns an error in JSON, instead of redirecting the user.

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Closes #357437 (closed)