Culling: ensure last_activity attr exists before use#365

Merged

Zsailer merged 2 commits intojupyter-server:masterfrom afshin:ensure_last_activity

Dec 23, 2020

+195-14

Commits on Dec 22, 2020

Port over jupyter/notebook#5355 and other fixes
afshin
committed

Commits on Dec 23, 2020

Follow up to fix CI
afshin
committed