tests: Added a check for unaccessible global known_hosts
Verify that the check process will not fail if the global known_hosts
file is not accessible and the local known_hosts file contain the host.
Signed-off-by: Anderson Toshiyuki Sasaki <email@example.com>
Reviewed-by: Andreas Schneider <firstname.lastname@example.org>
Reviewed-by: Jakub Jelen <email@example.com>
(cherry picked from commit 8e42ed82201f4c42dcbc0726a2304d8ab69179dc)