v1.9.0rc2

What's Changed

• Phase 1: self-intersecting polyslab by @weiliangjin2021 in #678
• customize SSL verify For http requests by @lei-flex in #667
• add pre-commit hook for black by @tylerflex in #656
• Run tests on PR into pre/ branches by @momchil-flex in #686
• adjoint improvements for 1.9.0rc2 by @tylerflex in #676
• fixes for 1.9.0rc2 docs by @tylerflex in #684
• Including package data in setup.py by @momchil-flex in #687
• Try gdspy vertices loading if gdstk loading fails by @tylerflex in #683
• Tyler/fast json string by @tylerflex in #689
• add jax as dev requirement by @tylerflex in #695

Full Changelog: v1.9.0rc1...v1.9.0rc2