Tweak the GDScript error message about passed argument type mismatch

This makes it less confusing.

This closes https://github.com/godotengine/godot-proposals/issues/670.

modules/gdscript/gdscript_parser.cpp

@@ -7336,8 +7336,8 @@ GDScriptParser::DataType GDScriptParser::_reduce_function_call_type(const Operat
 		} else if (!_is_type_compatible(arg_types[i - arg_diff], par_type, true)) {
 			// Supertypes are acceptable for dynamic compliance
 			if (!_is_type_compatible(par_type, arg_types[i - arg_diff])) {
-				_set_error("At \"" + callee_name + "()\" call, argument " + itos(i - arg_diff + 1) + ". Assigned type (" +
-								   par_type.to_string() + ") doesn't match the function argument's type (" +
+				_set_error("At \"" + callee_name + "()\" call, argument " + itos(i - arg_diff + 1) + ". The passed argument's type (" +
+								   par_type.to_string() + ") doesn't match the function's expected argument type (" +
 								   arg_types[i - arg_diff].to_string() + ").",
 						p_call->line);
 				return DataType();