Publish homebrew tap via GoReleaser

[nderjung]

Feature request summary

This issue tracks adding brew to the list of distributables from GoReleaser for KraftKit.

A new tap repository has been created at https://github.com/unikraft/homebrew-cli

Which will ultimately allow for KraftKit to be installed via:

brew install unikraft/cli/kraftkit

A new entry in GoReleaser's config needs to be added to the stable channel:

brews:
  - description: "Build and use highly customized and ultra-lightweight unikernels."
    name: kraftkit
    install: |
      bin.install "kraft"
    homepage: "https://kraftkit.sh"
    license: "BSD-3-Clause"
    skip_upload: auto
    tap:
      owner: unikraft
      name: homebrew-cli
      token: "{{ .Env.GITHUB_TOKEN }}"

More details can be found here: https://goreleaser.com/customization/homebrew/?h=tap

Additionally, though not in the code snippet above,bison and gsed for macOS are required. These need to be injected into the new configurable toolchain since they are installed at alternative (homebrew-specific) PATHs.

The following additional brew dependencies need to be part of the install:

brew install gnu-sed
brew install make
brew install m4
brew install gawk
brew install grep
brew install wget
brew install qemu
brew install socat
# ...for compiling x86_64 Unikernels
brew install x86_64-elf-binutils
brew install x86_64-elf-gcc
# ...for compiling aarch-64 Unikernels
brew install aarch64-elf-binutils
brew install aarch64-elf-gcc

Describe alternatives

No response

Related architectures

None

Related platforms

None

Additional context

Not sure if the environmental variable GITHUB_TOKEN will work.

GitHub-Depends-On: #675