Let git push-pending skip GUI when nothing found

bin/git-push-pending

@@ -4,6 +4,9 @@ repositories=$(git-pending "$@" \
 	| grep '^ahead' \
 	| lua -e 'for line in io.lines() do print(line:match("[^/]+$")); print((line:gsub("^[^ ]* ", ""))) end' \
 )
+if [ -z "$repositories" ]
+then exit
+fi
 echo "$repositories" \
 	| zenity --list --column Repository --column Path --text "Repositories that need pushing:" --multiple --title "Git" --separator ';' --width 800 --height 300 --print-column=2 2>/dev/null \
 	| tr ';' '\n' \