iotests/207: Filter host fingerprint

iotests/207: Filter host fingerprint

Commit e3296cc796aeaf319f3ed4e064ec309baf5e4da4 made the ssh block
driver's error message for fingerprint mismatches more verbose, so it
now prints the actual host key fingerprint and the key type.

iotest 207 tests such errors, but was not amended to filter that
fingerprint (which is host-specific), so do it now.  Filter the key
type, too, because I guess this too can differ depending on the host
configuration.

Fixes: e3296cc796aeaf319f3ed4e064ec309baf5e4da4
       ("block: print the server key type and fingerprint on failure")
Reported-by: John Snow <jsnow@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220318125304.66131-3-hreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>