[build] Clear out old supported Xcode versions (#37875)
[build] Clear out old supported Xcode versions (#37875)

* [build] Clear out old supported Xcode versions

* restore 12.3 and 12.4
roambotics/swift,tkremenek/swift,apple/swift,roambotics/swift,tkremenek/swift,ahoppen/swift,benlangmuir/swift,JGiola/swift,xwu/swift,tkremenek/swift,gregomni/swift,benlangmuir/swift,JGiola/swift,glessard/swift,apple/swift,apple/swift,rudkx/swift,ahoppen/swift,glessard/swift,tkremenek/swift,xwu/swift,xwu/swift,xwu/swift,glessard/swift,hooman/swift,hooman/swift,tkremenek/swift,ahoppen/swift,gregomni/swift,roambotics/swift,atrick/swift,parkera/swift,ahoppen/swift,parkera/swift,atrick/swift,parkera/swift,roambotics/swift,apple/swift,atrick/swift,rudkx/swift,JGiola/swift,hooman/swift,parkera/swift,tkremenek/swift,benlangmuir/swift,atrick/swift,gregomni/swift,rudkx/swift,rudkx/swift,tkremenek/swift,JGiola/swift,benlangmuir/swift,benlangmuir/swift,ahoppen/swift,roambotics/swift,xwu/swift,rudkx/swift,gregomni/swift,xwu/swift,xwu/swift,benlangmuir/swift,JGiola/swift,atrick/swift,glessard/swift,JGiola/swift,apple/swift,roambotics/swift,glessard/swift,hooman/swift,parkera/swift,parkera/swift,hooman/swift,parkera/swift,rudkx/swift,hooman/swift,glessard/swift,apple/swift,parkera/swift,gregomni/swift,hooman/swift,ahoppen/swift,atrick/swift,gregomni/swift