Include PID in default logging_context_format_string
Include PID in default logging_context_format_string

Change-Id: I1d0458ecb1314c941d8c72a54c76f9e554ef4348

zzicewind/oslo.log,JioCloud/oslo.log,meganjbaker/oslo.log,akash1808/oslo.log,openstack/oslo.log,dims/oslo.log,magic0704/oslo.log,varunarya10/oslo.log