ui: Add Scrollbar component (#18927)

Closes #ISSUE

Release Notes:

- N/A

crates/ui/src/components.rs

@@ -18,6 +18,7 @@ mod popover;
 mod popover_menu;
 mod radio;
 mod right_click_menu;
+mod scrollbar;
 mod settings_container;
 mod settings_group;
 mod stack;
@@ -49,6 +50,7 @@ pub use popover::*;
 pub use popover_menu::*;
 pub use radio::*;
 pub use right_click_menu::*;
+pub use scrollbar::*;
 pub use settings_container::*;
 pub use settings_group::*;
 pub use stack::*;