### 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)

case TYPE_BVEC4:
									member_type = TYPE_BOOL;
									break;
								case TYPE_VEC4:
									member_type = TYPE_FLOAT;
									break;
								case TYPE_IVEC4:
									member_type = TYPE_INT;
									break;
								case TYPE_UVEC4:
									member_type = TYPE_UINT;
									break;
								case TYPE_MAT4:
									member_type = TYPE_VEC4;
									break;
								default:
									break;
							}
							break;
						default: {
							_set_error(vformat(RTR("An object of type '%s' can't be indexed."), (expr->get_datatype() == TYPE_STRUCT ? expr->get_datatype_name() : get_datatype_name(expr->get_datatype()))));
							return nullptr;
						}
					}
				}
				OperatorNode *op = alloc_node<OperatorNode>();
				op->op = OP_INDEX;
				op->return_cache = member_type;
				op->struct_name = member_struct_name;
				op->arguments.push_back(expr);