Update sketch-beta to 46.2,44476 (#4268)

Casks/sketch-beta.rb

@@ -1,11 +1,11 @@
 cask 'sketch-beta' do
-  version '46.1,44463'
-  sha256 '27419a98af0d51de8efa5389dc1d720b68af7122a09e1bcd8ca81e38c8ab0f88'
+  version '46.2,44476'
+  sha256 '7201d619a174c880a3101a7491d16a1220ba0771c40e18446b304b86a98494ad'
 
   # hockeyapp.net/api/2/apps/0172d48cceec171249a8d850fb16276b was verified as official when first introduced to the cask
   url "https://rink.hockeyapp.net/api/2/apps/0172d48cceec171249a8d850fb16276b/app_versions/#{version.after_comma}?format=zip"
   appcast 'https://rink.hockeyapp.net/api/2/apps/0172d48cceec171249a8d850fb16276b',
-          checkpoint: '0880f28b6c386c0bcb7facbf5accc723de48f91564fa194b59adcab9e31c6532'
+          checkpoint: '64f7fad4de82e19850eb506f7a3d2949117f105c311b359f1d2b1a6dc96a0a20'
   name 'Sketch'
   homepage 'https://www.sketchapp.com/beta/'