message: add changelog entry for subdomain support
diff: @@ -35,6 +35,7 @@ encrypt content for other users.
  responses should now behave correctly.
  - `handlePendingSignIn` now takes a second parameter which is the
  signed authentication response token. Thanks to @muneebm for this!
  +- Proofs now support subdomains.
  ## [17.2.0]
  