remove_packages: remove a package's -debug package too

An AUR package built with makepkg's debug option comes with pkg-debug,
which nothing depends on, so pacman -Rns leaves it behind. voxtype-debug
then conflicts with voxtype-bin-debug, and update fails on machines
installed before voxtype-bin replaced voxtype. Found by
30-upgrade-from-baseline at 0c0ddf5.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/utils.bats

@@ -173,6 +173,22 @@ esac'
   called sudo pacman -Rns --noconfirm vim
 }
 
+@test "remove_packages removes a package's -debug package too, even on its own" {
+  # voxtype-debug outlives voxtype, and conflicts with voxtype-bin-debug
+  stub pacman '
+[ "$1" = -Qq ] || exit 1
+case "$2" in
+  voxtype|voxtype-debug|herdr-debug) echo "$2" ;;
+  *) exit 1 ;;
+esac'
+  stub sudo
+  source "$REPO/utils.sh"
+
+  run remove_packages voxtype herdr vim
+  [ "$status" -eq 0 ]
+  called sudo pacman -Rns --noconfirm voxtype voxtype-debug herdr-debug
+}
+
 @test "remove_packages does nothing when nothing is installed" {
   stub pacman 'exit 1'
   stub sudo