Remove ableton-live-beta (#4759)

Casks/ableton-live-beta.rb

@@ -1,14 +0,0 @@
-cask 'ableton-live-beta' do
-  version '9.7.1b3'
-  sha256 '8d5744c93b7d1f0346427a8bf945bdc7343b6f707eb4d9450365552557d54f80'
-
-  url "http://cdn2-downloads.ableton.com/channels/#{version}/ableton_live_beta_#{version.no_dots}_64.dmg"
-  name 'Ableton Live Beta'
-  homepage 'https://www.ableton.com/en/live/'
-
-  app "Ableton Live #{version.major_minor} Beta.app"
-
-  zap delete: '~/Library/*/*[Aa]bleton*',
-      rmdir:  '~/Music/Ableton/Factory Packs'
-  #:trash => '~/Music/Ableton/User Library'
-end