### Godot version

4.0.beta16

### System information

Windows 10 Pro x64, GLES3, RTX 3080 Ti (528.02)

### Issue description

In Compatibility/GLES3 back-end, shaders which use a uniform to get the normal roughness buffer cannot compile. For example, the shader:
```glsl
shader_type spatial;

uniform sampler2D normal_roughness_texture : hint_normal_roughness_texture;

void fragment() {
    vec4 sample = texture(normal_roughness_texture, UV);
}
```
results in an error in the output:
```
  drivers/gles3/shader_gles3.cpp:242 - SceneShaderGLES3: Fragment shader compilation failed:
  0(890) : error C1503: undefined variable "normal_roughness_buffer"
  
  drivers/gles3/shader_gles3.cpp:342 - Method/function failed.
```

If I switch over to the Mobile or Forward+ backends, there is no shader compilation error.

### Steps to reproduce

Open the attached reproduction in the 4.0.beta16 editor.

When the scene is opened, the error is produced automatically:
1. Open `scene.tscn`
2. Open Output to review error

When the scene is saved with any changes made to the shader, the same error is also produced:
1. Open `scene.tscn`
2. Open `example.gdshader` in the shader editor.
3. Make a compile-able change to the shader.
4. Save the scene
5. Open Output to review the error

### Minimal reproduction project

[NormalRoughnessTexture_GLES3_Error.zip](https://github.com/godotengine/godot/files/10534253/NormalRoughnessTexture_GLES3_Error.zip)

String type_name = p_datatype_a == TYPE_STRUCT ? p_datatype_name_a : get_datatype_name(p_datatype_a);
		if (p_array_size_a > 0) {
			type_name += "[";
			type_name += itos(p_array_size_a);
			type_name += "]";
		}
		String type_name2 = p_datatype_b == TYPE_STRUCT ? p_datatype_name_b : get_datatype_name(p_datatype_b);
		if (p_array_size_b > 0) {
			type_name2 += "[";
			type_name2 += itos(p_array_size_b);
			type_name2 += "]";
		}
		_set_error(vformat(RTR("Invalid assignment of '%s' to '%s'."), type_name2, type_name));
	}
	return result;
}
bool ShaderLanguage::_compare_datatypes_in_nodes(Node *a, Node *b) {
	return _compare_datatypes(a->get_datatype(), a->get_datatype_name(), a->get_array_size(), b->get_datatype(), b->get_datatype_name(), b->get_array_size());
}
bool ShaderLanguage::_parse_function_arguments(BlockNode *p_block, const FunctionInfo &p_function_info, OperatorNode *p_func, int *r_complete_arg) {
	TkPos pos = _get_tkpos();
	Token tk = _get_token();
	if (tk.type == TK_PARENTHESIS_CLOSE) {
		return true;
	}
	_set_tkpos(pos);
	while (true) {
		if (r_complete_arg) {
			pos = _get_tkpos();
			tk = _get_token();