### 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)

}
			for (int i = 0; i < 4; i++) {
				expression.remove_at(next_op);
			}
		} else {
			if (next_op < 1 || next_op >= (expression.size() - 1)) {
				_set_parsing_error();
				ERR_FAIL_V(nullptr);
			}
			OperatorNode *op = alloc_node<OperatorNode>();
			op->op = expression[next_op].op;
			if (expression[next_op - 1].is_op) {
				_set_parsing_error();
				ERR_FAIL_V(nullptr);
			}
			if (_is_operator_assign(op->op)) {
				String assign_message;
				if (!_validate_assign(expression[next_op - 1].node, p_function_info, &assign_message)) {
					_set_error(assign_message);
					return nullptr;
				}
			}
			if (expression[next_op + 1].is_op) {
				
				
				
				
				_set_parsing_error();
			}
			op->arguments.push_back(expression[next_op - 1].node);