curl "$API_BASE_URL/v1/org/$ORG_ID/contexts/sign-in/$CTX_ID/modules/whitelistings/active" \ -H "x-auth-token: $NETGRAPH_API_TOKEN"
[ "AA:BB:CC:00:00:01", "AA:BB:CC:00:00:07" ]
Return MACs that currently have an active session in the Context.