Move prerelease label to rc1
Move prerelease label to rc1

dotnet/buildtools,crummel/dotnet_buildtools,dotnet/buildtools,ericstj/buildtools,stephentoub/buildtools,ericstj/buildtools,dotnet/buildtools,dotnet/buildtools,weshaggard/buildtools,nguerrera/buildtools,stephentoub/buildtools,crummel/dotnet_buildtools,nguerrera/buildtools,nguerrera/buildtools,ericstj/buildtools,crummel/dotnet_buildtools,ericstj/buildtools,weshaggard/buildtools,crummel/dotnet_buildtools,weshaggard/buildtools,stephentoub/buildtools,stephentoub/buildtools,nguerrera/buildtools,weshaggard/buildtools