Update oslo.context to 2.16.0
Update oslo.context to 2.16.0

Change-Id: I1841d1f77d4da52c488d5779f47362cb6feedd35
Depends-on: I7a0d2d80f9965ccb3253af553a334e35b584f2e7

openstack/rpm-packaging,openstack/rpm-packaging