qa/1696: change wait for pmproxy startup logic
qa/1696: change wait for pmproxy startup logic

Borrowed from qa/1695.

adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp