Added the test case for Port Channel cleanup into runtest.sh (sonic-net#157)

* Added the test case for Port Channel cleanup.
Test make sure cleanup happens of Port-channel Kernel devices.
This test case track the fixes done by PR:
sonic-net/sonic-swss#1407
sonic-net/sonic-swss#1159

Signed-off-by: Abhishek Dosi <[email protected]>

* Address Review Comments

Signed-off-by: Abhishek Dosi <[email protected]>

Author: abdosi

scripts/vs/buildimage-vs-image/runtest.sh

@@ -53,6 +53,7 @@ cacl/test_cacl_function.py \
 dhcp_relay/test_dhcp_relay.py \
 lldp/test_lldp.py \
 ntp/test_ntp.py \
+pc/test_po_cleanup.py \
 route/test_default_route.py \
 snmp/test_snmp_cpu.py \
 snmp/test_snmp_interfaces.py \