Draft: Resolve "[Backend] Filter compliance violations by branch names"

What does this MR do and why?

Describe in detail what your merge request does and why.

Query plans

Query	Time
Default	774.566 ms
Default + by_target_branches: ['main']	507.444 ms 🐇
Default + by_target_branches: ['main', 'master', 'staging']	1.134 s 🐢

How to set up and validate locally

mr = MergeRequest.find_by_title("Merge protected into main");
group = mr.project.group
user = User.find_by_id(1)

filters = { merged_after: Date.parse("2022-04-19"), merged_before: Date.parse("2022-05-19"), sort: 'SEVERITY_LEVEL_ASC', target_branches: ['main', 'master', 'staging'] }

# Add .to_sql to get the raw query
::ComplianceManagement::MergeRequests::ComplianceViolationsFinder.new(current_user: user, group: group, params: filters).execute

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #358411 (closed)