This PR depends on https://github.com/sonic-net/sonic-swss/pull/2737 merge first.
**What I did**
Add orchagent watchdog to monitor and alert orchagent stuck issue.
**Why I did it**
Currently SONiC monit system only monit orchagent process exist or not. If orchagent process stuck and stop processing, current monit can't find and report it.
**How I verified it**
Pass all UT.
Add new UT https://github.com/sonic-net/sonic-mgmt/pull/8306 to check watchdog works correctly.
Manually test, after pause orchagent with 'kill -STOP <pid>', check there are warning message exist in log:
Apr 28 23:36:41.504923 vlab-01 ERR swss#supervisor-proc-watchdog-listener: Process 'orchagent' is stuck in namespace 'host' (1.0 minutes).
**Details if related**
Heartbeat message PR: https://github.com/sonic-net/sonic-swss/pull/2737
UT PR: https://github.com/sonic-net/sonic-mgmt/pull/8306
44427a2f6b