1. Since upgrade python to 3.7, some urllib3 warnings come out during
execution, because missing disconnection when using request by docker
library, it's not affect script execution, therefore ignore them first.
2. Replication tests failed in nightly due to new UI code, some element
locators are not valid anymore;
3. Remove switch scanner test steps, since Clair was removed.
Signed-off-by: danfengliu <danfengl@vmware.com>
