### 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)

_set_error(RTR("Expected an identifier or '[' after type."));
					} else {
						_set_error(RTR("Expected a function name after type."));
					}
					return ERR_PARSE_ERROR;
				}
				if (shader->structs.has(name) || _find_identifier(nullptr, false, constants, name) || has_builtin(p_functions, name)) {
					_set_redefinition_error(String(name));
					return ERR_PARSE_ERROR;
				}
				tk = _get_token();
				if (tk.type != TK_PARENTHESIS_OPEN) {
					if (type == TYPE_VOID) {
						_set_error(RTR("Expected '(' after function identifier."));
						return ERR_PARSE_ERROR;
					}
					
					while (true) {
						ShaderNode::Constant constant;
						constant.name = name;
						constant.type = is_struct ? TYPE_STRUCT : type;
						constant.type_str = struct_name;
						constant.precision = precision;
						constant.initializer = nullptr;
						constant.array_size = array_size;
						if (tk.type == TK_BRACKET_OPEN) {
							Error error = _parse_array_size(nullptr, constants, false, nullptr, &constant.array_size, &unknown_size);
							if (error != OK) {
								return error;
							}