fix(Nav): Hide flyout example and props (#6329)

Author: nicolethoen

packages/react-core/src/components/Nav/NavItem.tsx

@@ -27,9 +27,9 @@ export interface NavItemProps extends Omit<React.HTMLProps<HTMLAnchorElement>, '
   onClick?: NavSelectClickHandler;
   /** Component used to render NavItems if  React.isValidElement(children) is false */
   component?: React.ReactNode;
-  /** Flyout sub-navigation of a nav item */
+  /** @hide Flyout sub-navigation of a nav item */
   flyout?: React.ReactNode;
-  /** Callback when flyout is opened or closed */
+  /** @hide Callback when flyout is opened or closed */
   onShowFlyout?: () => void;
 }
 

packages/react-core/src/components/Nav/examples/Nav.md

@@ -504,7 +504,7 @@ class NavTertiaryList extends React.Component {
 }
 ```
 
-### Flyout
+<!--- ### Flyout
 
 A flyout should be another `Nav` component with the `subnav` variant. Press `space` or `right arrow` to open a flyout using the keyboard, use `tab` to navigate between items, and press `escape` or `left arrow` to close a flyout.
 
@@ -566,4 +566,4 @@ NavWithFlyout = () => {
     </Nav>
   );
 };
-```
+``` -->