### Godot version

v4.0.beta13.official [caacade56]

### System information

Linux Ubuntu 20.04 with Unity desktop

### Issue description

When calling an undefined function in the shader editor with argument(s), such as `undefined_function(1)`, the error reads:

> Too many arguments for "undefined_function()" call. Expected at most 0 but received 1.

instead of the expected:

> No matching function found for: 'undefined_function'.

This is possibly a regression introduced in https://github.com/godotengine/godot/issues/18225, since the latter was focused on the arguments part.

To avoid such regression in the future, consider adding a unit test with this case (and, in fact, unit tests for the other signature errors too if there are not already).

### Steps to reproduce

1. Create a shader resource and open the shader editor
2. Enter `undefined_function(1);` in the fragment() definition

### Minimal reproduction project

N/A
if (!_validate_varying_assign(shader->varyings[identifier], &error)) {
								_set_error(error);
								return nullptr;
							}
						} else {
							switch (var.stage) {
								case ShaderNode::Varying::STAGE_UNKNOWN: {
									if (var.type < TYPE_INT) {
										if (current_function == varying_function_names.vertex) {
											_set_error(vformat(RTR("Varying with '%s' data type may only be used in the 'fragment' function."), get_datatype_name(var.type)));
										} else {
											_set_error(vformat(RTR("Varying '%s' must be assigned in the 'fragment' function first."), identifier));
										}
										return nullptr;
									}
								} break;
								case ShaderNode::Varying::STAGE_VERTEX:
									if (current_function == varying_function_names.fragment || current_function == varying_function_names.light) {
										var.stage = ShaderNode::Varying::STAGE_VERTEX_TO_FRAGMENT_LIGHT;
									}
									break;
								case ShaderNode::Varying::STAGE_FRAGMENT:
									if (current_function == varying_function_names.light) {
										var.stage = ShaderNode::Varying::STAGE_FRAGMENT_TO_LIGHT;
									}
									break;
								default:
									break;
							}
						}