[swift-stdlib-tool] Fix finding sibling directories (#41110)
[swift-stdlib-tool] Fix finding sibling directories (#41110)


roambotics/swift,gregomni/swift,roambotics/swift,rudkx/swift,glessard/swift,benlangmuir/swift,rudkx/swift,atrick/swift,roambotics/swift,roambotics/swift,JGiola/swift,rudkx/swift,glessard/swift,JGiola/swift,rudkx/swift,rudkx/swift,rudkx/swift,apple/swift,apple/swift,gregomni/swift,benlangmuir/swift,roambotics/swift,atrick/swift,gregomni/swift,atrick/swift,ahoppen/swift,ahoppen/swift,apple/swift,glessard/swift,roambotics/swift,benlangmuir/swift,glessard/swift,JGiola/swift,ahoppen/swift,ahoppen/swift,apple/swift,JGiola/swift,JGiola/swift,apple/swift,gregomni/swift,benlangmuir/swift,atrick/swift,glessard/swift,gregomni/swift,ahoppen/swift,glessard/swift,JGiola/swift,gregomni/swift,apple/swift,benlangmuir/swift,atrick/swift,atrick/swift,benlangmuir/swift,ahoppen/swift