editor: Dismiss mouse context menus on selections change (#28729)

Closes #ISSUE

Adds an extra subscription for mouse context menus (i.e. right click context menu) so that when selections change in the editor while the context menu is open (e.g. with vim motions), the context menu closes.

Release Notes:

- N/A

crates/editor/src/editor.rs

@@ -1787,6 +1787,7 @@ impl Editor {
         cx: &mut Context<Self>,
     ) {
         self.mouse_context_menu = Some(MouseContextMenu::new(
+            self,
             crate::mouse_context_menu::MenuPosition::PinnedToScreen(position),
             context_menu,
             None,