Starting with autojump 21.0.3+ there is no file autojump in etc/
directory, so we source the autojump.zsh file directly. Version 20 has
it as well, so there should be no problems with earlier versions.
Comments on autojump's update in homebrew:
5da9c4d5eb (Library)/Formula/autojump.rb
If you manually install autojump as advised by the autojump README by running
the install.sh script, it will install by default to $HOME/.autojump.
Add an extra case in the zsh autojump plugin to find the new file and stop a
syntax error in the else clause every time a new zsh starts (running brew when
brew does not exist).