[Localization] Use testing fixture in DefToYAMLConverter
[Localization] Use testing fixture in DefToYAMLConverter

Makes it easy to setup convertion from def-to-yaml and remove
a temporary file.

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