Revert "permit onion v3 authentication of Tor Browser"

This reverts commit 97ff68a6.

Allows login accross multiple VMs. Therefore potential cross VM tracking identifier.

https://phabricator.whonix.org/T996#20096

etc/onion-grater-merger.d/30_whonix-default.yml

@@ -31,8 +31,6 @@
       - 'consensus/valid-after'
       - 'consensus/valid-until'
       - 'consensus/fresh-until'
-    onion_client_auth_add:
-      - '.+'
   confs:
     __owningcontrollerprocess:
   events: