CI: use iperf3, refactor Iperf_Module

Main improvements:

• simplification of the CI iperf testing framework - rework and cleanup of the Iperf_Module function, remove redundant functions
• introduce TCP target rate check - add TCP tests with rate check to SA-B200 and SA-AW2S pipelines
• improve analysis of the iperf3 test reports (analysis from json reports, check receiver report for each test)
• undeploy gNB/UE after each OTA test run - should reduce interference caused by UE which remained ON after the test

TBD:

• RAN-LTE-TDD-LTEBOX and RAN-LTE-FDD-LTEBOX: check TCP rate?
• RAN-L2-Sim-Test-4G - lower tested UL bitrate?
• recheck SABOX target TCP
  • E1+F1 testcase, we can set higher TCP target rates (UL: 8 -> 15 Mbps, DL: 20 -> 30 Mbps)
• recheck AW2S target TCP
  • we can set higher TCP target rates (UL: 1 -> 2 Mbps/UE, DL: 4 -> 6 Mbps/UE)
• RAN-RF-Sim-Test-4G --> Could not analyze from server log
  • FEMBMS does not work with iperf3 because of the control channel (TCP messages) during test init
  • log collection from the test - to be fixed
• undeploy gNB/UE after each testcase
  • SA-AERIAL-CN5G
  • SA-OAIUE-CN5G
  • SA-AW2S-CN5G
  • LTE-TDD-2x2
  • LTE-FDD-OAIUE-OAICN4G
• --get-server-report for TCP and BIDIR testcases - could be skipped?
• Possibility to use JSON reports from iperf3 for all test cases? --> not possible with UDP iperf3 version 3.9
  • iperf 3.9 (cJSON 1.7.13)
  • TCP - check sender/receiver "bits_per_second"
  • BIDIR - check sender/receiver UL/DL "bits_per_second"
  • UDP - receiver "bits_per_second" reports 0
• Check iperf3 analysis function - correct checks done?
• Iperf server ID usage
• TCP bitrate check for B200 pipelines
• RAN-L2-Sim-Test-4G --> Could not analyze from server log - log looks OK
• RAN-SA-B200_Module-SABOX-Container --> add TCP with target rate check, so we will test UDP, TCP, BIDIR

Iperf3 test list: