fix: carry over fixed_window attribute to overrides

[pubalokta]

By submitting a PR to this repository, you agree to the terms within the Auth0 Code of Conduct. Please see the contributing guidelines for how to create and submit a high-quality PR for this repo.

Description

We realised that overriding limits seemed to bring back the sliding window behaviour if the limit was set to fixed_window:
During testing we created an override setting the limit to 100 RPS. The moment the override hit the configuration, the behavior changed, we saw the sliding window behavior back in place.

After removing the override we were back to the fixed_window behavior.

References

Include any links supporting this change such as a:

• GitHub Issue/PR number addressed or fixed
• Auth0 Community post
• StackOverflow post
• Support forum thread
• Related pull requests/issues from other repos

If there are no references, simply delete this section.

Testing

Tested live after applying an override:

• This change adds test coverage for new/changed/fixed functionality

Checklist

• I have added documentation for new/changed functionality in this PR or in auth0.com/docs
• All active GitHub checks for tests, formatting, and security are passing
• The correct base branch is being used, if not the default branch