fix some warnings in SupervisionTest.cpp (#15885)
fix some warnings in SupervisionTest.cpp (#15885)


arangodb/arangodb,arangodb/arangodb,arangodb/arangodb,wiltonlazary/arangodb,wiltonlazary/arangodb,arangodb/arangodb,wiltonlazary/arangodb,wiltonlazary/arangodb,arangodb/arangodb,wiltonlazary/arangodb,arangodb/arangodb,wiltonlazary/arangodb,wiltonlazary/arangodb,wiltonlazary/arangodb,arangodb/arangodb,arangodb/arangodb