I am really not sure why the caller even should have the option to set
this. We should always use the correct isolation type based on the
privileges the server runs under never the client. podman-remote build
seems to send the default based on its local privs which was wrong as
well. To fix this I also changed the client to send the default if the
isolation flag is not set.
Fixes#22109
Signed-off-by: Paul Holzinger <pholzing@redhat.com>