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).
1 job for wip/mlundblad/fixed-eds-and-folks in 4 minutes and 10 seconds (queued for 1 second)
latest
Status Name Job ID Coverage
  Test
failed flatpak #1335797
flatpak

00:04:10

 
Name Stage Failure
failed
flatpak Test
Uploading artifacts for failed job
Uploading artifacts...
WARNING: gnome-maps-git.flatpak: no matching files
WARNING: repo.tar: no matching files
WARNING: .flatpak-builder/build/gnome-maps/_flatpak_build/meson-logs/meson-log.txt: no matching files
WARNING: .flatpak-builder/build/gnome-maps/_flatpak_build/meson-logs/testlog.txt: no matching files
ERROR: No files to upload
Cleaning up file based variables
ERROR: Job failed: exit code 1