Add centos-9-stream job

Add octavia-v2-dsvm-scenario-centos-9-stream

Add extra args to the "scp" command to authorize the pubkey exchange
with a cirros VM.
Detect the openssh client version to enable the use of the SCP protocol
(starting with openssh 8.7, the SFTP protocol is the default protocol
with scp, SFTP is not supported by Cirros) when sending files to the
cirros VM.

Depends-On: https://review.opendev.org/828189

Change-Id: I689a50e6762fd22e1aaec8aa84ff5b075ff5bd45
3 files changed