ipatests: Improve test_commands reliability
    
    Sometimes ssh command gets stuck, running manually without passing a command
    to be executed this is returned:
    
    ```
    $ ssh -o PasswordAuthentication=no -o IdentitiesOnly=yes \
      -o StrictHostKeyChecking=no -l testsshuser \
      -i /tmp/tmp.rQIT3KYScX master.ipa.test
    Could not chdir to home directory /home/testsshuser: No such file or directory
    ```
    
    This commit forces the homedir creation and adds a timeout to ssh.
    
    Signed-off-by: Armando Neto <abiagion@redhat.com>
    Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>