Update thunderbird-daily to 61.0a1 (#5429)
Update thunderbird-daily to 61.0a1 (#5429)

* Update thunderbird-daily to 59.0b2

* Update thunderbird-daily.rb

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