Add support of UtGnTrigger in AtsRSUsSimulator test suite
fix certificate and key extensions fix default certificates and key search path
Separate TC_SEC_ITSS_SND_CAM_11_BV: TC_SEC_ITSS_SND_CAM_11_01_BV for PICS_SEC_SHA256 & TC_SEC_ITSS_SND_CAM_11_02_BV for PICS_SEC_SHA384
Provide ssp in lower layer parameters