cask/url: accept Class for using in Cask::URL#initialize

[gibfahn]

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Commits (oldest to newest)

b4feaf2 cask/url: accept Class for using in Cask::URL#initialize

#15754 fixed Cask::URL::DSL#initialize, but we also need to fix Cask::URL#initialize as that takes the same parameters.

Error:

Error: Cask 'mycask' definition is invalid: 'url' stanza failed
  with: Parameter 'using': Expected type T.nilable(Symbol), got type Class
  with value MyCustomDownloadStrategy
Caller:
  /opt/homebrew/Library/Homebrew/vendor/bundle/ruby/2.6.0/gems/sorbet-runtime-0.5.10461/lib/types/private/methods/call_validation.rb:113

Refs: #15750

[gibfahn]

cc/ @MikeMcQuaid as this is basically the same as #15754

[Bo98]

Thanks!