Add release note for rejecting absolute paths in DevTools file reads

Author: adilburaksen

packages/devtools_app/release_notes/NEXT_RELEASE_NOTES.md

@@ -19,6 +19,10 @@ To learn more about DevTools, check out the
   widget with a different number of children, for example when toggling a
   panel in or out of the layout. -
   [#9822](https://github.com/flutter/devtools/pull/9822)
+* Rejected absolute paths in DevTools server file reads so they stay within
+  the `~/.flutter-devtools/` directory and cannot resolve to arbitrary files
+  on disk. -
+  [#9844](https://github.com/flutter/devtools/pull/9844)
 
 ## Inspector updates