This is resolved in patch Spectrum_10.02.02.PTF_10.2.202 for 10.2.2. This is tentatively scheduled to be fixed in 10.2.3 and 10.3 and above.
The release notes show:
Symptom: In Trap Based Continuous Discovery, on receiving SNMPv2c trap, device is being
modeled as SNMPv1 i.e. with V1 community name.
Resolution: On receiving SNMPv2c trap, device is modeled with SNMPv2c community name.
Once the patch is installed, the SS will utilize the v2 community name for the discovery process when a v2 trap is received.