[test/Syntax/round_trip_stdlib.swift] Exclude the test for an ASAN build
[test/Syntax/round_trip_stdlib.swift] Exclude the test for an ASAN build

It is too slow, rdar://64215520

atrick/swift,stephentyrone/swift,allevato/swift,parkera/swift,rudkx/swift,tkremenek/swift,rudkx/swift,parkera/swift,airspeedswift/swift,glessard/swift,ahoppen/swift,jckarter/swift,CodaFi/swift,xwu/swift,JGiola/swift,allevato/swift,stephentyrone/swift,xwu/swift,rudkx/swift,xwu/swift,jmgc/swift,ahoppen/swift,JGiola/swift,gregomni/swift,glessard/swift,hooman/swift,allevato/swift,jckarter/swift,benlangmuir/swift,JGiola/swift,tkremenek/swift,roambotics/swift,benlangmuir/swift,parkera/swift,parkera/swift,glessard/swift,gregomni/swift,apple/swift,hooman/swift,CodaFi/swift,airspeedswift/swift,tkremenek/swift,parkera/swift,nathawes/swift,hooman/swift,glessard/swift,xwu/swift,allevato/swift,tkremenek/swift,airspeedswift/swift,apple/swift,JGiola/swift,stephentyrone/swift,parkera/swift,roambotics/swift,apple/swift,nathawes/swift,xwu/swift,stephentyrone/swift,glessard/swift,jckarter/swift,atrick/swift,tkremenek/swift,rudkx/swift,stephentyrone/swift,jmgc/swift,parkera/swift,apple/swift,roambotics/swift,nathawes/swift,gregomni/swift,airspeedswift/swift,stephentyrone/swift,jckarter/swift,jmgc/swift,hooman/swift,benlangmuir/swift,hooman/swift,jmgc/swift,ahoppen/swift,xwu/swift,benlangmuir/swift,tkremenek/swift,stephentyrone/swift,jmgc/swift,JGiola/swift,jckarter/swift,hooman/swift,ahoppen/swift,CodaFi/swift,jckarter/swift,benlangmuir/swift,airspeedswift/swift,nathawes/swift,allevato/swift,CodaFi/swift,atrick/swift,gregomni/swift,CodaFi/swift,roambotics/swift,gregomni/swift,allevato/swift,roambotics/swift,nathawes/swift,tkremenek/swift,apple/swift,ahoppen/swift,parkera/swift,airspeedswift/swift,ahoppen/swift,CodaFi/swift,jckarter/swift,atrick/swift,CodaFi/swift,hooman/swift,atrick/swift,jmgc/swift,benlangmuir/swift,glessard/swift,atrick/swift,nathawes/swift,JGiola/swift,airspeedswift/swift,allevato/swift,roambotics/swift,xwu/swift,rudkx/swift,rudkx/swift,apple/swift,gregomni/swift,jmgc/swift,nathawes/swift