Update WindowsBuild.md
Update WindowsBuild.md

Simplify the CMake invocation for Swift and match `build-script`.
lorentey/swift,practicalswift/swift,stephentyrone/swift,shahmishal/swift,glessard/swift,karwa/swift,ahoppen/swift,jmgc/swift,rudkx/swift,apple/swift,aschwaighofer/swift,tkremenek/swift,CodaFi/swift,practicalswift/swift,apple/swift,allevato/swift,atrick/swift,apple/swift,allevato/swift,stephentyrone/swift,hooman/swift,xedin/swift,jckarter/swift,jmgc/swift,parkera/swift,jckarter/swift,lorentey/swift,shajrawi/swift,hooman/swift,nathawes/swift,nathawes/swift,practicalswift/swift,shajrawi/swift,xwu/swift,xwu/swift,hooman/swift,jmgc/swift,devincoughlin/swift,karwa/swift,allevato/swift,xedin/swift,shahmishal/swift,aschwaighofer/swift,parkera/swift,tkremenek/swift,ahoppen/swift,practicalswift/swift,devincoughlin/swift,gregomni/swift,shahmishal/swift,shahmishal/swift,devincoughlin/swift,lorentey/swift,harlanhaskins/swift,CodaFi/swift,JGiola/swift,jmgc/swift,stephentyrone/swift,sschiau/swift,nathawes/swift,roambotics/swift,allevato/swift,stephentyrone/swift,harlanhaskins/swift,aschwaighofer/swift,rudkx/swift,devincoughlin/swift,nathawes/swift,parkera/swift,allevato/swift,JGiola/swift,jckarter/swift,xedin/swift,stephentyrone/swift,rudkx/swift,lorentey/swift,airspeedswift/swift,airspeedswift/swift,benlangmuir/swift,airspeedswift/swift,gribozavr/swift,jckarter/swift,aschwaighofer/swift,glessard/swift,apple/swift,gribozavr/swift,sschiau/swift,CodaFi/swift,gregomni/swift,stephentyrone/swift,hooman/swift,airspeedswift/swift,karwa/swift,gregomni/swift,CodaFi/swift,xwu/swift,glessard/swift,shahmishal/swift,sschiau/swift,jckarter/swift,harlanhaskins/swift,atrick/swift,devincoughlin/swift,tkremenek/swift,benlangmuir/swift,benlangmuir/swift,nathawes/swift,xedin/swift,xedin/swift,rudkx/swift,gribozavr/swift,parkera/swift,sschiau/swift,airspeedswift/swift,aschwaighofer/swift,aschwaighofer/swift,allevato/swift,jckarter/swift,xedin/swift,CodaFi/swift,ahoppen/swift,devincoughlin/swift,xwu/swift,parkera/swift,hooman/swift,hooman/swift,gregomni/swift,lorentey/swift,sschiau/swift,shahmishal/swift,jmgc/swift,harlanhaskins/swift,harlanhaskins/swift,glessard/swift,xwu/swift,karwa/swift,atrick/swift,atrick/swift,parkera/swift,practicalswift/swift,jmgc/swift,practicalswift/swift,rudkx/swift,ahoppen/swift,CodaFi/swift,roambotics/swift,karwa/swift,harlanhaskins/swift,nathawes/swift,nathawes/swift,rudkx/swift,gribozavr/swift,shahmishal/swift,lorentey/swift,tkremenek/swift,atrick/swift,gregomni/swift,glessard/swift,benlangmuir/swift,shajrawi/swift,xwu/swift,shahmishal/swift,tkremenek/swift,JGiola/swift,JGiola/swift,airspeedswift/swift,gregomni/swift,roambotics/swift,karwa/swift,karwa/swift,tkremenek/swift,roambotics/swift,karwa/swift,roambotics/swift,stephentyrone/swift,shajrawi/swift,apple/swift,parkera/swift,jckarter/swift,gribozavr/swift,sschiau/swift,devincoughlin/swift,tkremenek/swift,sschiau/swift,JGiola/swift,xwu/swift,shajrawi/swift,airspeedswift/swift,allevato/swift,JGiola/swift,shajrawi/swift,gribozavr/swift,gribozavr/swift,hooman/swift,sschiau/swift,ahoppen/swift,lorentey/swift,jmgc/swift,devincoughlin/swift,apple/swift,aschwaighofer/swift,parkera/swift,xedin/swift,shajrawi/swift,harlanhaskins/swift,xedin/swift,roambotics/swift,lorentey/swift,atrick/swift,practicalswift/swift,ahoppen/swift,shajrawi/swift,glessard/swift,benlangmuir/swift,benlangmuir/swift,gribozavr/swift,practicalswift/swift,CodaFi/swift