### 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)

return ERR_PARSE_ERROR;
						}
						Node *expr = _parse_and_reduce_expression(nullptr, constants);
						if (!expr) {
							return ERR_PARSE_ERROR;
						}
						if (expr->type != Node::TYPE_CONSTANT) {
							_set_error(RTR("Expected constant expression after '='."));
							return ERR_PARSE_ERROR;
						}
						ConstantNode *cn = static_cast<ConstantNode *>(expr);
						uniform.default_value.resize(cn->values.size());
						if (!convert_constant(cn, uniform.type, uniform.default_value.ptrw())) {
							_set_error(vformat(RTR("Can't convert constant to '%s'."), get_datatype_name(uniform.type)));
							return ERR_PARSE_ERROR;
						}
						tk = _get_token();
					}
					shader->uniforms[name] = uniform;
#ifdef DEBUG_ENABLED
					if (check_warnings && HAS_WARNING(ShaderWarning::UNUSED_UNIFORM_FLAG)) {
						used_uniforms.insert(name, Usage(tk_line));
					}
#endif 
					
					uniform_scope = ShaderNode::Uniform::SCOPE_LOCAL;
					if (tk.type != TK_SEMICOLON) {
						_set_expected_error(";");
						return ERR_PARSE_ERROR;
					}