### Godot version

4.0.rc6.mono.official

### System information

macOS 12.0.1

### Issue description

Just a minor visual issue.

When opening an empty directory the focus highlight is drawn incorrectly. It looks like the UI is drawing a smaller rectangle within the main rect:
<img width="1058" alt="Bildschirmfoto 2023-02-28 um 14 13 31" src="https://user-images.githubusercontent.com/11627131/221868794-7450606d-e758-4104-8f33-182d9779d7f8.png">


This behavior also changes when you hover over other items in the view, so I'm not sure if this a general issue with the focus highlighting or just an issue in the directory view:
<img width="1052" alt="Bildschirmfoto 2023-02-28 um 14 32 54" src="https://user-images.githubusercontent.com/11627131/221869308-4756f26e-cda2-4057-be1e-7439030895dc.png">


### Steps to reproduce

1. New Project
2. Browse
3. Create Folder
4. Click or Tab to set focus on the empty directory view

### Minimal reproduction project

N/A
glBufferData(GL_ARRAY_BUFFER, lc * 6 * sizeof(float), geometry.ptr(), GL_STATIC_DRAW);
			glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, oc->index_buffer);
			glBufferData(GL_ELEMENT_ARRAY_BUFFER, 3 * lc * sizeof(uint16_t), indices.ptr(), GL_STATIC_DRAW);
			glBindBuffer(GL_ARRAY_BUFFER, 0);
			glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
		}
	}
	
	Vector<int> sdf_indices;
	if (p_points.size()) {
		if (p_closed) {
			sdf_indices = Geometry2D::triangulate_polygon(p_points);
			oc->sdf_is_lines = false;
		} else {
			int max = p_points.size();
			sdf_indices.resize(max * 2);
			int *iw = sdf_indices.ptrw();
			for (int i = 0; i < max; i++) {
				iw[i * 2 + 0] = i;
				iw[i * 2 + 1] = (i + 1) % max;
			}
			oc->sdf_is_lines = true;
		}
	}
	if (oc->sdf_index_count != sdf_indices.size() && oc->sdf_point_count != p_points.size() && oc->sdf_vertex_array != 0) {
		glDeleteVertexArrays(1, &oc->sdf_vertex_array);
		GLES3::Utilities::get_singleton()->buffer_free_data(oc->sdf_vertex_buffer);
		GLES3::Utilities::get_singleton()->buffer_free_data(oc->sdf_index_buffer);
		oc->sdf_vertex_array = 0;
		oc->sdf_vertex_buffer = 0;