Disable zpool_import_missing_003_pos
Rarely observed failure of zpool_import_missing_003_pos during
automated testing due to timeout. Disable the test case until
it can be improved.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov>
Signed-off-by: George Melikov <mail@gmelikov.ru>
Issue #6839
Closes #6840