add missing type param

Author: supersaiyansubtlety

enigma-cli/src/test/java/org/quiltmc/enigma/command/ValidateArgNamesTest.java

@@ -22,7 +22,7 @@ void validate() {
 
 	private static Set<String> validateArgs(String cmdName, ImmutableList<Argument<?>> args) {
 		final Set<String> argNames = new HashSet<>();
-		for (final Argument arg : args) {
+		for (final Argument<?> arg : args) {
 			final String argName = arg.getName();
 
 			Assertions.assertFalse(