Update ableton-live-beta to 9.7b4 (#2671)

Casks/ableton-live-beta.rb

@@ -1,14 +1,8 @@
 cask 'ableton-live-beta' do
   version '9.7b4'
+  sha256 '5bc6d02891df5702af956f29efab70223fd5ca92a3746b96d84bc1abd8cd8ac0'
 
-  if Hardware::CPU.is_32_bit?
-    sha256 '48dbe8d0648a62e5778d7a5551205cee91abd0cacc5e76ad8bc94a810b217683'
-    url "http://cdn2-downloads.ableton.com/channels/#{version}/ableton_live_beta_#{version.no_dots}_32.dmg"
-  else
-    sha256 '5bc6d02891df5702af956f29efab70223fd5ca92a3746b96d84bc1abd8cd8ac0'
-    url "http://cdn2-downloads.ableton.com/channels/#{version}/ableton_live_beta_#{version.no_dots}_64.dmg"
-  end
-
+  url "http://cdn2-downloads.ableton.com/channels/#{version}/ableton_live_beta_#{version.no_dots}_64.dmg"
   name 'Ableton Live Beta'
   homepage 'https://ableton.com/en/live'
   license :commercial