Removed MainMenu.Sub docs.

dev-docs/docs/@excalidraw/excalidraw/api/children-components/main-menu.mdx

@@ -167,35 +167,3 @@ function App() {
 | Prop | Type | Required | Default | Description |
 | --- | --- | :-: | :-: | --- |
 | `children ` | `React.ReactNode` | Yes | - | The content of the `Menu Group` |
-
-### MainMenu.Sub
-
-The MainMenu component now supports submenus. To render a submenu, you can use `MainMenu.Sub`, `MainMenu.Sub.Trigger`, `MainMenu.Sub.Content` and `MainMenu.Sub.Item`. Note that `MainMenu.Sub.Trigger` and `MainMenu.Sub.Content` must be direct children of `MainMenu.Sub`.
-
-```jsx live
-function App() {
-  return (
-    <div style={{ height: "500px" }}>
-      <Excalidraw>
-        <MainMenu>
-          <MainMenu.Sub>
-            <MainMenu.Sub.Trigger>Submenu</MainMenu.Sub.Trigger>
-            <MainMenu.Sub.Content>
-              <MainMenu.Sub.Item
-                onSelect={() => window.alert("Submenu item 1")}
-              >
-                Submenu item 1
-              </MainMenu.Sub.Item>
-              <MainMenu.Sub.Item
-                onSelect={() => window.alert("Submenu item 2")}
-              >
-                Submenu item 2
-              </MainMenu.Sub.Item>
-            </MainMenu.Sub.Content>
-          </MainMenu.Sub>
-        </MainMenu>
-      </Excalidraw>
-    </div>
-  );
-}
-```