Use querystring as source of truth for filters on vulnerability report

What does this MR do?

On the vulnerability report, there are filter dropdowns that filter the vulnerability list:

Previously, the source of truth (what determines which dropdown items are selected) could either be the selected dropdown items or the querystring, depending on the user action. It's hard to explain in text, so please watch this video explanation (with audio):

Untitled

Does this MR meet the acceptance criteria?

Conformity

• 📋 Does this MR need a changelog?
  • I have included a changelog entry.
  • I have not included a changelog entry because this is refactor work.
• [-] Documentation (if required)
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• [-] Style guides
• [-] Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
• [-] Informed Infrastructure department of a default or new setting change, if applicable per definition of done