### 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)

} else if (tk.type == TK_PERIOD) {
#ifdef DEBUG_ENABLED
				uint32_t prev_keyword_completion_context = keyword_completion_context;
				keyword_completion_context = CF_UNSPECIFIED;
#endif
				DataType dt = expr->get_datatype();
				String st = expr->get_datatype_name();
				if (!expr->is_indexed() && expr->get_array_size() > 0) {
					completion_class = TAG_ARRAY;
					if (p_block != nullptr) {
						p_block->block_tag = SubClassTag::TAG_ARRAY;
					}
					Node *call_expression = _parse_and_reduce_expression(p_block, p_function_info);
					if (p_block != nullptr) {
						p_block->block_tag = SubClassTag::TAG_GLOBAL;
					}
					if (!call_expression) {
						return nullptr;
					}
					expr = call_expression;
					break;
				}
				StringName identifier;
				if (_get_completable_identifier(p_block, dt == TYPE_STRUCT ? COMPLETION_STRUCT : COMPLETION_INDEX, identifier)) {
					if (dt == TYPE_STRUCT) {
						completion_struct = st;
					} else {
						completion_base = dt;
					}
				}