Add persistent system app string

Author: victorhuangwq

microsoft-edge/webview2/release-notes/index.md

@@ -227,7 +227,7 @@ Added a new `ScreenCaptureStarting` event.  This event is raised whenever the We
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 #### Other changes
 
-* The Microsoft Edge WebView2 Runtime is no longer listed in Windows **Settings** > **Apps** > **Installed apps**.
+* The Microsoft Edge WebView2 Runtime is no longer listed in Windows **Settings** > **Apps** > **Installed apps** because it is a persistent system component.
 
 
 <!-- end of Nov 2024 Release SDK -->