maturin 0.12.11 on Rust Cargo

What's Changed

Switch back to toml_edit by @messense in #839
Stop testing Python 3.6 on CI by @messense in #840
Package license files in .dist-info by @messense in #837
Upgrade test crates to pyo3 0.16 by @messense in #841
Fix maturin sdist --manifest-path for workspace project by @messense in #843
migrate to github container registry by @konstin in #845
Update docs for docker image registry change by @messense in #846
Update workspace memebers for sdist local dependencies by @messense in #844
Remove PYO3_NO_PYTHON hack for Windows by @messense in #848
Remove Windows abi3 python lib link hack by @messense in #851
Fix workspace members in subdirectory for sdist local dependencies by @messense in #852
Add cache to Cirrus CI by @messense in #853
Add -r option as a short alias for --release by @messense in #854

Full Changelog: v0.12.10...v0.12.11