Update docker-edge to 18.04.0-ce-rc2-mac61,23890 (#5490)
Update docker-edge to 18.04.0-ce-rc2-mac61,23890 (#5490)


mahori/homebrew-versions,pkq/homebrew-versions,404NetworkError/homebrew-versions,pkq/homebrew-versions,404NetworkError/homebrew-versions,Ngrd/homebrew-versions,lantrix/homebrew-versions,Ngrd/homebrew-versions,lantrix/homebrew-versions,rogeriopradoj/homebrew-versions,rogeriopradoj/homebrew-versions,caskroom/homebrew-versions,victorpopkov/homebrew-versions,victorpopkov/homebrew-versions,mahori/homebrew-cask-versions,caskroom/homebrew-versions