Merge routes on identical crags with identical names / grades

Both Crags are:

• in the identical country
• at the identical location
• contain identical routes(identical name, identical grade) on identical sectors

hence they should be merged.

Main Crag: https://www.8a.nu/crags/sportclimbing/serbia-yugoslavia/valjevo/routes

Crag to be merged: https://www.8a.nu/crags/sportclimbing/unknown/valjevo/routes