Advanced search issues label facet refactor

What does this MR do and why?

We are working on unifying url params across the whole gitlab. Labels has been one of the params identified as one that needs to be updated.

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

How to set up and validate locally

1. Make sure advanced search is installed and enabled
2. Make sure you enable zoekt.
3. Visit search page http://gdk.test:3000/search?scope=issues&search=test
4. Toggle some label filters on and of and see it working.

Related to #466730 (closed)