### Godot version

4.0 beta 10

### System information

Windows 11 Vulkan

### Issue description

Looked through the issues list, but couldn't find something like this, sorry in advance if this has already been reported.

There is a few cases (in the pictures below) where list of Actions in Input Map may not always show a scrollbar even if the actions list overflows (I imagine this could also happen for the widget that Input Map uses).

![image](https://user-images.githubusercontent.com/39958198/210003566-cf60dbaf-921f-485b-b0a9-51ffc28d0244.png)

![New Bitmap image](https://user-images.githubusercontent.com/39958198/210004079-8eb2e6a1-0cf5-4a7c-8905-a4e3cfd0ec5d.png)

![image](https://user-images.githubusercontent.com/39958198/210004165-a6b6790b-248a-4f68-b4d0-b44b25afdf4f.png)

![image](https://user-images.githubusercontent.com/39958198/210004537-aca52194-a464-48b9-b818-24782706de45.png)


### Steps to reproduce

The pictures are clearer than anything I could write here: "a picture is worth 1000 words"

### Minimal reproduction project

N/A
ClassDB::bind_method(D_METHOD("set_h_scroll_enabled", "h_scroll"), &Tree::set_h_scroll_enabled);
	ClassDB::bind_method(D_METHOD("is_h_scroll_enabled"), &Tree::is_h_scroll_enabled);
	ClassDB::bind_method(D_METHOD("set_v_scroll_enabled", "h_scroll"), &Tree::set_v_scroll_enabled);
	ClassDB::bind_method(D_METHOD("is_v_scroll_enabled"), &Tree::is_v_scroll_enabled);
	ClassDB::bind_method(D_METHOD("set_hide_folding", "hide"), &Tree::set_hide_folding);
	ClassDB::bind_method(D_METHOD("is_folding_hidden"), &Tree::is_folding_hidden);
	ClassDB::bind_method(D_METHOD("set_enable_recursive_folding", "enable"), &Tree::set_enable_recursive_folding);
	ClassDB::bind_method(D_METHOD("is_recursive_folding_enabled"), &Tree::is_recursive_folding_enabled);
	ClassDB::bind_method(D_METHOD("set_drop_mode_flags", "flags"), &Tree::set_drop_mode_flags);
	ClassDB::bind_method(D_METHOD("get_drop_mode_flags"), &Tree::get_drop_mode_flags);
	ClassDB::bind_method(D_METHOD("set_allow_rmb_select", "allow"), &Tree::set_allow_rmb_select);
	ClassDB::bind_method(D_METHOD("get_allow_rmb_select"), &Tree::get_allow_rmb_select);
	ClassDB::bind_method(D_METHOD("set_allow_reselect", "allow"), &Tree::set_allow_reselect);
	ClassDB::bind_method(D_METHOD("get_allow_reselect"), &Tree::get_allow_reselect);
	ADD_PROPERTY(PropertyInfo(Variant::INT, "columns"), "set_columns", "get_columns");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "column_titles_visible"), "set_column_titles_visible", "are_column_titles_visible");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "allow_reselect"), "set_allow_reselect", "get_allow_reselect");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "allow_rmb_select"), "set_allow_rmb_select", "get_allow_rmb_select");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "hide_folding"), "set_hide_folding", "is_folding_hidden");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "enable_recursive_folding"), "set_enable_recursive_folding", "is_recursive_folding_enabled");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "hide_root"), "set_hide_root", "is_root_hidden");
	ADD_PROPERTY(PropertyInfo(Variant::INT, "drop_mode_flags", PROPERTY_HINT_FLAGS, "On Item,In Between"), "set_drop_mode_flags", "get_drop_mode_flags");
	ADD_PROPERTY(PropertyInfo(Variant::INT, "select_mode", PROPERTY_HINT_ENUM, "Single,Row,Multi"), "set_select_mode", "get_select_mode");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "scroll_horizontal_enabled"), "set_h_scroll_enabled", "is_h_scroll_enabled");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "scroll_vertical_enabled"), "set_v_scroll_enabled", "is_v_scroll_enabled");
	ADD_SIGNAL(MethodInfo("item_selected"));
	ADD_SIGNAL(MethodInfo("cell_selected"));
	ADD_SIGNAL(MethodInfo("multi_selected", PropertyInfo(Variant::OBJECT, "item", PROPERTY_HINT_RESOURCE_TYPE, "TreeItem"), PropertyInfo(Variant::INT, "column"), PropertyInfo(Variant::BOOL, "selected")));
	ADD_SIGNAL(MethodInfo("item_mouse_selected", PropertyInfo(Variant::VECTOR2, "position"), PropertyInfo(Variant::INT, "mouse_button_index")));
	ADD_SIGNAL(MethodInfo("empty_clicked", PropertyInfo(Variant::VECTOR2, "position"), PropertyInfo(Variant::INT, "mouse_button_index")));