### 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(vformat(RTR("Unknown array size is forbidden in that context.")));
			return ERR_PARSE_ERROR;
		}
		if (r_unknown_size != nullptr) {
			*r_unknown_size = true;
		}
	} else {
		int array_size = 0;
		if (!tk.is_integer_constant() || ((int)tk.constant) <= 0) {
			_set_tkpos(pos);
			Node *n = _parse_and_reduce_expression(p_block, p_function_info);
			if (n) {
				if (n->type == Node::TYPE_VARIABLE) {
					VariableNode *vn = static_cast<VariableNode *>(n);
					if (vn) {
						ConstantNode::Value v;
						DataType data_type;
						bool is_const = false;
						_find_identifier(p_block, false, p_function_info, vn->name, &data_type, nullptr, &is_const, nullptr, nullptr, &v);
						if (is_const) {
							if (data_type == TYPE_INT) {
								int32_t value = v.sint;
								if (value > 0) {
									array_size = value;
								}
							} else if (data_type == TYPE_UINT) {
								uint32_t value = v.uint;
								if (value > 0U) {
									array_size = value;
								}