maps-service: Drop dark and aerial from the fallback service

As we have removed the dark and aerial tiles from the service
file, also remove them from the fallback (used when the online
one is unavailable).
2 jobs for master in 15 minutes and 45 seconds
Status Job ID Name Coverage
  Test
passed #1329255
flatpak
flatpak

00:13:34

 
  Deploy
passed #1329256
nightly

00:02:11