### Tested versions

- Reproducible in: v4.2.stable.arch_linux
- Not Reproducible in: v4.1.3.stable.official [f06b6836a]

### System information

Garuda Linux (2.6.19-2)

### Issue description

A minor issue where UI Icons are not rendering on the Group Editor window, attaching a screenshot for reference:
![Screenshot_604](https://github.com/godotengine/godot/assets/22623256/c366164a-3d9a-4dcf-97a0-199b5a5a7ecc)

The icons were expected for Buttons like Add, Remove, Filter, etc.

### Steps to reproduce

Select any Node and go to the `Node` panel, click `Manage Groups` and the window will open.

### Minimal reproduction project (MRP)

Minor issue, easily reproducible following the above steps.
vbc_remove->add_child(nodes_to_remove);
	nodes_to_remove->set_v_size_flags(Control::SIZE_EXPAND_FILL);
	nodes_to_remove->set_hide_root(true);
	nodes_to_remove->set_hide_folding(true);
	nodes_to_remove->set_select_mode(Tree::SELECT_MULTI);
	nodes_to_remove->add_theme_constant_override("draw_guides", 1);
	HBoxContainer *remove_filter_hbc = memnew(HBoxContainer);
	remove_filter_hbc->add_theme_constant_override("separate", 0);
	vbc_remove->add_child(remove_filter_hbc);
	remove_filter = memnew(LineEdit);
	remove_filter->set_h_size_flags(Control::SIZE_EXPAND_FILL);
	remove_filter->set_placeholder(TTR("Filter Nodes"));
	remove_filter_hbc->add_child(remove_filter);
	remove_filter->connect("text_changed", callable_mp(this, &GroupDialog::_remove_filter_changed));
	group_empty = memnew(Label());
	group_empty->set_theme_type_variation("HeaderSmall");
	group_empty->set_text(TTR("Empty groups will be automatically removed."));
	group_empty->set_vertical_alignment(VERTICAL_ALIGNMENT_CENTER);
	group_empty->set_horizontal_alignment(HORIZONTAL_ALIGNMENT_CENTER);
	group_empty->set_autowrap_mode(TextServer::AUTOWRAP_WORD_SMART);
	group_empty->set_custom_minimum_size(Size2(100 * EDSCALE, 0));
	nodes_to_remove->add_child(group_empty);
	group_empty->set_anchors_and_offsets_preset(Control::PRESET_FULL_RECT, Control::PRESET_MODE_KEEP_SIZE, 8 * EDSCALE);
	set_title(TTR("Group Editor"));
	error = memnew(AcceptDialog);
	add_child(error);
	error->set_ok_button_text(TTR("Close"));
	_add_group_text_changed("");
}
void GroupsEditor::_add_group(const String &p_group) {