v0.37.0 - Maintenance release, test stability

Tests

• pytest-xdist support in #522
• test stability improvements in #522
  • retry_until() tests: Relax clock in assert.
  • tests/test_pane.py::test_capture_pane_start: Use retry_until() to poll, improve correctness of test.

Full Changelog: v0.36.0...v0.37.0