### 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)

return p_char == ' ' || p_char == '\t';
}
bool ShaderPreprocessor::is_char_end(char32_t p_char) {
	return p_char == '\n' || p_char == 0;
}
String ShaderPreprocessor::vector_to_string(const LocalVector<char32_t> &p_v, int p_start, int p_end) {
	const int stop = (p_end == -1) ? p_v.size() : p_end;
	const int count = stop - p_start;
	String result;
	result.resize(count + 1);
	for (int i = 0; i < count; i++) {
		result[i] = p_v[p_start + i];
	}
	result[count] = 0; 
	return result;
}
String ShaderPreprocessor::tokens_to_string(const LocalVector<Token> &p_tokens) {
	LocalVector<char32_t> result;
	for (const Token &token : p_tokens) {
		result.push_back(token.text);
	}
	return vector_to_string(result);
}
void ShaderPreprocessor::process_directive(Tokenizer *p_tokenizer) {