Fix error with theme generation

lib/apply_scheme_to_template.sh

@@ -9,15 +9,15 @@ fi
 source $MO_PATH
 
 rgb_r() {
-	echo "$((0x${MO_FUNCTION_ARGS[0]:0:2}))"
+	printf "$((0x${MO_FUNCTION_ARGS[0]:0:2}))"
 }
 
 rgb_g() {
-	echo "$((0x${MO_FUNCTION_ARGS[0]:2:2}))"
+	printf "$((0x${MO_FUNCTION_ARGS[0]:2:2}))"
 }
 
 rgb_b() {
-	echo "$((0x${MO_FUNCTION_ARGS[0]:4:4}))"
+	printf "$((0x${MO_FUNCTION_ARGS[0]:4:4}))"
 }
 
 set -a # All variables after this will be exported