### 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)

break;
										} else if (curly && tk.type == TK_CURLY_BRACKET_CLOSE) {
											decl.initializer.push_back(n);
											break;
										} else {
											if (curly) {
												_set_expected_error("}", ",");
											} else {
												_set_expected_error(")", ",");
											}
											return ERR_PARSE_ERROR;
										}
									}
									if (unknown_size) {
										decl.size = decl.initializer.size();
										constant.array_size = decl.initializer.size();
									} else if (decl.initializer.size() != constant.array_size) {
										_set_error(RTR("Array size mismatch."));
										return ERR_PARSE_ERROR;
									}
								}
								array_size = constant.array_size;
								ConstantNode *expr = memnew(ConstantNode);
								expr->datatype = constant.type;
								expr->struct_name = constant.type_str;
								expr->array_size = constant.array_size;
								expr->array_declarations.push_back(decl);
								constant.initializer = static_cast<ConstantNode *>(expr);
							} else {
#ifdef DEBUG_ENABLED