Add new repository filter for favourited repositories

[bergamin]

Is your feature request related to a problem? Please describe.
No

Describe the solution you'd like
Add an extra repository filter which would filter all favourited repositories. This would make it easier to keep the repository filter consistent even after cleaning session storage

Describe alternatives you've considered
What I do today is to select all the 84 122 repositories under my watch in the filter and keep a copy of the json extracted from the session storage as a backup in case of need

Additional context
This would ensure that whenever I favourite a new repo, it will immediately show up in the hub without having to change the filters again