Tried update cask formula to 2.0.0

[rafilkmp3]

I tried to to update a formula to 2.0.0 but seens something changed and wont pass on tests...

https://github.com/Homebrew/homebrew-core/pull/53964/checks?check_run_id=629425938

[chenrui333]

@rafilkmp3 minor correction, is core formula instead of cask formula.

To echo his comment, there is more comprehensive discussion in this PR (Homebrew/homebrew-core#53959), it looks like the latest tfenv depends on latest bash rather than the system default bash.