### Godot version

v4.0.beta15.official [4fa6edc88]

### System information

Windows 10 (10.0.19045 Build 19045) | Forward+ | Vulkan API 1.3.206 | AMD Radeon RX 6800 XT

### Issue description

If there is a function with arguments within a `.gdshaderinc` file, then this function can not be used in other shaders that include this via a relative include. The error in the other shaders is "Too many arguments for "example()" call. Expected at most 0 but received 1". Using an absolute path for the include resolves the error.

**Note:** The relative include *does* work in the special case of both files being in the project root.

### Steps to reproduce

1. Put a shader and a shader-include file into a subdirectory
2. Write a function with arguments in the shader-include file
3. Include that file in the shader
4. Try to use the function

### Minimal reproduction project

[shader-include-bug.zip](https://github.com/godotengine/godot/files/10508745/shader-include-bug.zip)

bool changed = false;
	bool warnings_enabled = GLOBAL_GET("debug/shader_language/warnings/enable").booleanize();
	if (warnings_enabled != saved_warnings_enabled) {
		saved_warnings_enabled = warnings_enabled;
		changed = true;
	}
	bool treat_warning_as_errors = GLOBAL_GET("debug/shader_language/warnings/treat_warnings_as_errors").booleanize();
	if (treat_warning_as_errors != saved_treat_warning_as_errors) {
		saved_treat_warning_as_errors = treat_warning_as_errors;
		changed = true;
	}
	bool update_flags = false;
	for (int i = 0; i < ShaderWarning::WARNING_MAX; i++) {
		ShaderWarning::Code code = (ShaderWarning::Code)i;
		bool value = GLOBAL_GET("debug/shader_language/warnings/" + ShaderWarning::get_name_from_code(code).to_lower());
		if (saved_warnings[code] != value) {
			saved_warnings[code] = value;
			update_flags = true;
			changed = true;
		}
	}
	if (update_flags) {
		saved_warning_flags = (uint32_t)ShaderWarning::get_flags_from_codemap(saved_warnings);
	}
	if (p_validate && changed && shader_editor && shader_editor->get_edited_shader().is_valid()) {
		shader_editor->validate_script();
	}
}
void TextShaderEditor::_check_for_external_edit() {