Fix name of group for feature flags related to The Auth team

What does this MR do and why?

We renamed group 'Access' to 'Authentication and Authorization', see gitlab-com/www-gitlab-com!96097 (merged).

This MR fixes outdated group attribute for feature flags that Authentication and Authorization owns.

https://app.periscopedata.com/app/gitlab/792066/Engineering-::-Feature-Flags

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