Drop the idea of elephant-all by default

It adds 80mb to the ISO for stuff we don't use out of the box. Better
just to have elephant-all for those who want it later.

migrations/1777542438.sh

@@ -1,6 +0,0 @@
-echo "Replace coterie of individual Elephant packages with the single elephant-all package"
-
-if omarchy-pkg-present omarchy-walker; then
-  yes | sudo pacman -S --needed elephant-all walker
-  sudo pacman -R --noconfirm omarchy-walker
-fi