pymanopt/pymanopt: 2.2.0

What's Changed Re-enable build of stable docs by @nkoep in https://github.com/pymanopt/pymanopt/pull/228 Add JAX backend by @nkoep in https://github.com/pymanopt/pymanopt/pull/206 Add utility function to check Hessian operators by @nkoep in https://github.com/pymanopt/pymanopt/pull/230 Migrate from versioneer to setuptools-scm by @nkoep in https://github.com/pymanopt/pymanopt/pull/231 Add unitary group manifold by @nkoep in https://github.com/pymanopt/pymanopt/pull/232 and https://github.com/pymanopt/pymanopt/pull/233 chore: move metadata to pyproject.toml by @SauravMaheshkar in https://github.com/pymanopt/pymanopt/pull/236 Update zenodo to DOI umbrella badge by @nkoep in https://github.com/pymanopt/pymanopt/pull/238 feat(ci): add pip cache to CI by @SauravMaheshkar in https://github.com/pymanopt/pymanopt/pull/239 Add Complex valued manifolds by @antoinecollas in https://github.com/pymanopt/pymanopt/pull/125 New Contributors @SauravMaheshkar made their first contribution in https://github.com/pymanopt/pymanopt/pull/222 Full Changelog: https://github.com/pymanopt/pymanopt/compare/2.1.1...2.2.