One of the pep8 target dependencies must have updated,
causing a bunch of new lint errors in these categories:
- line length > 79 chars
- no whitespace after keyword
There was a race before a block_until_all_units_idle() where it
could blast through the check before it started removing the relation.
This ensures that it waits until something happens and then waits for it
to finish.
Samuel Walladge
Alex Kavanagh