### 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)

code = p_code;
	index = 0;
	line = 0;
	comment_line_open = 0;
	comments_open = 0;
	strings_open = 0;
}
ShaderPreprocessor::Token::Token() {
	text = 0;
	line = -1;
}
ShaderPreprocessor::Token::Token(char32_t p_text, int p_line) {
	text = p_text;
	line = p_line;
}
bool ShaderPreprocessor::is_char_word(char32_t p_char) {
	if ((p_char >= '0' && p_char <= '9') ||
			(p_char >= 'a' && p_char <= 'z') ||
			(p_char >= 'A' && p_char <= 'Z') ||
			p_char == '_') {
		return true;
	}
	return false;
}
bool ShaderPreprocessor::is_char_space(char32_t p_char) {