fish: config.fish: Use bind to revert fish 4.0 changes to keybindings

I prefer to move around with this granularity, I do not mind a few more
key presses for increased accuracy in deletion.

Signed-off-by: Nathan Chancellor <nathan@kernel.org>

fish/config.fish

@@ -65,5 +65,10 @@ if test -d $CARGO_HOME/bin
     fish_add_path -ag $CARGO_HOME/bin
 end
 
+# Undo fish 4.0 change to keybindings
+bind alt-backspace backward-kill-word
+bind alt-left backward-word
+bind alt-right forward-word
+
 # Make sure that sourcing config.fish always returns 0
 true