[SD-9] - Networking

Closes SD-9

This MR adds the 'Networking' feature to the Jamboree websites. The feature will allow users that opt-in (consent is required in order to share their contact information with other users) to add,accept,reject and remove contacts from a pool of attendees for a given event.

Furthermore the MR:

• recreates a jamboree app version of the pagination query filters that are used in HQ tables and customises the header to work with the networking feature
• adds a new networkingSlice to support the current and future extensions of the networking feature
• removes the outlines from the dropdownFilter search to improve user experience

Still in progress:

• Networking preferences update after the initial opt-in/opt-out (It will probably be in the accounts but TBD with Andrés)
• The Jamboree app navbar (currently implemented in order to match the design but I'm not sure if this supposed to be released before the actual Jamboree)