In D12999, the `reenter_if_this_is_arcanist_or_libphutil` function was removed. Now, as a result, I constantly hit the following exception:
```
Usage Exception: You are trying to run one copy of Arcanist on another copy of Arcanist. This operation is not supported. To execute Arcanist operations against this working copy, run `./bin/arc` (from the current working copy) not some other copy of 'arc' (you ran one from '/home/joshua/dotfiles/modules/phabricator/arcanist').
```
It would be nice to bring back the reentrant logic if it can be done without arcanist projects.