Bug-fix release in the 1.8.x series.

This release restores compatibility with networkx 2.8.3, which errors when
graph nodes might conflict with pydot parsing.

Full changelog: https://github.com/nipy/nipype/milestone/1.8.2?closed=1

  * ENH: Enable compression with Gunzip interface (https://github.com/nipy/nipype/pull/3472)
  * CI: Schedule weekly tests with cron (https://github.com/nipy/nipype/pull/3480)