[Bug] Compliance violations pagination doesn't show expected results

Summary

When sorting on the compliance violations report the pagination results aren't as expected. For example MERGED_AT_ASC returns results in the order of 1 day ago, 2 weeks ago and then 1 week ago on the next page.

Steps to reproduce

1. Have a GitLab Ultimate license.
2. Checkout the branch from this MR !82989 (merged)
3. Follow the setup steps in the MR above.
4. View the report at [GDK_HOST]/groups/[GROUP]/-/security/compliance_dashboard
5. Sort by Merged at and go to the next page and observe the results.
6. Repeat the last step.

What is the expected correct behavior?

The results should be ordered as expected. For example 1 day ago, 1 week ago and 2 weeks ago.

Possible fixes

Due to how our keyset pagination works we need to update the resolver to use offset pagination for merge request title and merged at sorting.

Implementation plan

backend - 2️⃣

1. Update http://gitlab.com/gitlab-org/gitlab/blob/master/ee/app/graphql/resolvers/compliance_management/merge_requests/compliance_violation_resolver.rb to fallback to offset pagination for certain sort options just like http://gitlab.com/gitlab-org/gitlab/blob/8b37e5107af85fc234ab8644bc98587b1cd94ef3/app/graphql/resolvers/base_issues_resolver.rb#L25-25.
2. Update specs to make sure it works.