Change activesupport version requirement to support Rails 7

What does this MR do and why?

Describe in detail what your merge request does and why.

Rails 7 MR raises the following warning on bundle install:

Your lockfile doesn't include a valid resolution.
You can fix this by regenerating your lockfile or manually editing the bad locked gems to a version that satisfies all dependencies.
The unmet dependencies are:
* activesupport (~> 6.1), dependency of gitlab_quality-test_tooling-0.8.0, unsatisfied by activesupport-7.0.4.3

Single commit Rails 7 MR fails: https://gitlab.com/gitlab-org/security/gitlab/-/merge_requests/3277

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