When Neovim does not know the Ruby version

If you are using:
- MacOS
- Neovim configured with Lua
- a Ruby version manager (for example chruby)
- zsh 

Then in case you cannot install for example RubyLSP because after installing a new version of Ruby it seems like Neovim does not recognize anymore the global Ruby version set and defaults to the system Ruby (which is ruby 2.6.x) you can fix this by adding the following to your Lua Neovim config:

vim.opt.shell = "zsh"