[tests] [asan] extend graceful stop flag to also stop syncd#2491

liat-grozovik merged 2 commits intosonic-net:mastersonic-net/sonic-swss:masterfrom

Yakiv-Huryk:tests-graceful-stop-syncdYakiv-Huryk/sonic-swss:tests-graceful-stop-syncdCopy head branch name to clipboard