Fix
* Use tempfile to get temp dir, rather than assuming /tmp ([`b42ebc2`](https://github.com/robinvandernoord/lib2fas-python/commit/b42ebc22d49c9168b8e4c632141d486c04192210) by [crmarsh](https://github.com/crmarsh))
* Revert linting changes to fixtures in 'tests' ([`8c717f5`](https://github.com/robinvandernoord/lib2fas-python/commit/8c717f5af25b9bea379aed2d6ee795b7cc5f7e36))