[screenlayout] Fix reference to changepaper script

screenlayout/.screenlayout/keyboard-and-bg.sh

@@ -1,3 +1,3 @@
 #!/bin/sh
-~/.bin/changepaper.sh
+~/.bin/changepaper
 setxkbmap -model pc105 -layout us,ru -option grp:ctrls_toggle -option caps:escape -option compose:ralt