protocol-engine goes down while fetching is-is metrics

[ashutshkumr]

https://github.com/open-traffic-generator/conformance/actions/runs/3928629942

IS-IS test has been skipped for now because of this

[ashutshkumr]

Logs from protocol-engine:

16-01,08:49:02,Profile,t116 : GetMetrics took 1 ms. (1213 microsecs) 
16-01,08:49:02,Profile,t138 : GetMetrics took 0 ms. (150 microsecs) 
16-01,08:49:03,ERROR,ISIS:   NSM socket Recv returned 0 on Read , closing socket. Error: [Success]
16-01,08:49:03,WARNING,ISIS:  NSM socket has failed to receive header. Closing socket.(Valid on protocol Stop)
16-01,08:49:03,ERROR,ARP Resolver:  NSM socket Recv returned 0 on Read , closing socket. Error: [No such file or directory]
16-01,08:49:03,WARNING,ARP Resolver: NSM socket has failed to receive header. Closing socket.(Valid on protocol Stop)

[ashutshkumr]

Release: 0.0.1-3698

Steps to reproduce:

git clone https://github.com/open-traffic-generator/conformance.git
cd conformance && git checkout 0ae0582

./do.sh topo new cpdp
./do.sh pregotest

# might have to run this multiple times to reproduce
./do.sh gotest -tags="feature"