Update homebrew install command to fix the error

[1matin]

The brew cask command is now deprecated and will cause an error as below:

% brew cask install telegram
Error: `brew cask` is no longer a `brew` command. Use `brew <command> --cask` instead.

I changed the command to the new form that homebrew accepts, which is brew ... --cask.

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✅ matamin
❌ overtake
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