Checks for an argument before setting a project

This fixes the bug where pushing esc whilst rofi menu is open would set
the project path to the main projects folder

bin/.bin/project-management/project-switch

@@ -33,6 +33,7 @@ function unset_project(){
 }
 
 function set_project(){
+	[ -z "$1" ] && exit 1
 	local switchto="$PROJECTS_PATH/$1"
 	if [ -d "$switchto" ]; then
 		if [ -L "$SYMLINC" ]; then