Add macOS homebrew package manager support

[zwimer]

Adding macOS homebrew support would allow users of the most-common package manager on macOS, brew, to update the app using brew upgrade as many other apps are updated.

This could also make the macOS quarantining issue easier as brew has built-in support for stripping the quarantine attributes via --no-quarantine or automatically for users who use HOMEBREW_CASK_OPTS_QUARANTINE.

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Adding homebrew support (the ability to use the brew package manager on macOS) can be done in 2 steps:

1. Create a tap repository (a github repo with a config file). The config file can be really simple, here is an example: https://github.com/vladdoster/homebrew-formulae/blob/main/Casks/vimari.rb
2. Add a Github Action to your main repo that creates PRs the tap repo on each new release. That is, the action will make a PR to update tap repo's config to point to the latest release (it will change version and sha256 in the example above). Here is a simple example/guide: https://extrawurst.medium.com/github-actions-homebrew-%EF%B8%8F-2789ae5023fd (I think you can make this even simpler by not updating the URL, if you use {version} in the URL like the example above.