Stop re-using client connections

The re-use of client connections in common/ssh.py depended on a bug in
tempest that causes leaked connections, see #1853264. Since that bug in
tempest was fixed, we now need to create a fresh connection every time
we need one.

Closes-Bug: #1858260
Related-Bug: #1853264

Co-Authored-By: Rodolfo Alonso Hernandez <ralonsoh@redhat.com>

Change-Id: I128340f14e7e9570b23721686504e12458e85773
1 file changed