Improve fish completions of brew bundle

[yoshida-ryuhei]

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Current status

• Current improvement of fish completions in brew bundle does not support all the sub commands, like install, list.

Change

• Add fish completions for brew bundle install/list.

[yoshida-ryuhei]

I missed the automatic generation of the shell completion file, but it has been corrected.

[MikeMcQuaid]

Thanks so much for your contribution! Without people like you submitting PRs we couldn't run this project. You rock, @yoshida-ryuhei!