chore: Update checking socket in kernel notification function

Line 174: I add a checking for 'socket.user' before use attribute 'username'. Without this checking, it's will cause an error if socket doesn't have 'use' attribute.
Merge pull request #44 from huyd/master

chore: Update checking socket in kernel notification function
Merge branch 'master' of github.com:mykabam/kabam-kernel