Provide list of Recently searched Groups/Projects in the dropdown filters for Global Search

The Original issue was raised about adding a similar feature based on starred porjects. From: https://twitter.com/EndlessMason/status/1296729251740344320

Problem to solve

Users typically want to search within Groups or Projects that they visit more often than other projects. These are likely to be used more frequently than other projects, so should appear before anything is typed. This functionality is similar to what appears in the Groups/Projects dropdowns in the top navbar.

Proposal

• Add frequently/recently visited Projects and Groups to the Project and Group dropdown filters on the search result page.
• Show up to 5 recent/frequent Groups/Projects

Release Notes

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