CI: create SA 2x2 pipeline

• add configuration files for new RAN-SA-2x2-Module-CN5G pipeline --> https://jenkins-oai.eurecom.fr/job/RAN-SA-2x2-Module-CN5G/
• tested bitrate (requested in iperf3 UDP test):

Testcase	60 MHz 2x2 TDD	100 MHz 2x2 TDD
DL UDP	200 Mbps	500 Mbps
UL UDP	130 Mbps	40 Mbps

TBD:

• fail to undeploy gNB as reported in #779
  • fixed by using RHEL images (fails only with Ubuntu docker image)
• check and adjust test packetloss/bitrate thresholds?
• 100 MHz testcase - 7DS2U or DDDSU TDD config to be used?
• 100 MHz testcase - low TCP BIDIR stats to be checked

Sender Bitrate DL   : 41.59 Mbps
Receiver Bitrate DL : 41.5 Mbps
Sender Bitrate UL   : 32.16 Mbps
Receiver Bitrate UL : 31.98 Mbps

• 60 MHz testcase - TCP BIDIR stats looks OK

Sender Bitrate DL   : 113.94 Mbps
Receiver Bitrate DL : 114.27 Mbps
Sender Bitrate UL   : 167.77 Mbps
Receiver Bitrate UL : 167.26 Mbps

• add SA-2x2 pipeline to parent pipeline