Reduce the list of existing tags

[akatsoulas]

Reduce the list of existing tags by:

• Deleting tags that are not used
• Deleting tags that are used only in archived questions
• Merging related tags by performing a fuzzy search

[akatsoulas]

PR https://github.com/mozilla/kitsune/pull/6335

[emilghittasv]

Prior to merging this PR I've created a couple of test data tags to match each criteria.

I can confirm that:

• I had created a tag called unusedTag which was not used anywhere and it got successfully deleted.
• I had created a tag called onlyUsedInArchive which was used only in archived questions and the tag was successfully deleted.
• I had created a tag called usedInLocked which was used only in locked questions and the tag was not deleted.
• I had created a tag called bothArchivedAndNonArchived which was used in both archived and non archived question and the tag was not deleted.
• I had created a tag called test which was used in multiple questions (non-archived) and the tag was not deleted.

Please note that the fuzzy merge was removed from the PR.

Moving this ticket inside the release column.