update to PyO3 v0.21 #36

Job	Run time
Build and test package / Generate build matrix	1s
Build and test package / Build source distribution	18s
Build and test package / build-and-test-binary (ubuntu-latest, 3.10, x64, x86_64, manylinux_2_17, true, false, _workflow_m...	1m 21s
Build and test package / build-and-test-binary (ubuntu-latest, 3.10, x64, aarch64, manylinux_2_17, false, quay.io/pypa/man...	2m 48s
Build and test package / build-and-test-binary (ubuntu-latest, 3.10, x64, x86_64-unknown-linux-musl, musllinux_1_1, false,...	1m 22s
Build and test package / build-and-test-binary (ubuntu-latest, 3.10, x64, aarch64-unknown-linux-musl, musllinux_1_1, false...	2m 13s
Build and test package / build-and-test-binary (macos-latest, 3.10, arm64, universal2-apple-darwin, auto, true, false, _wo...	1m 3s
Build and test package / build-and-test-binary (windows-latest, 3.10, x64, x64, auto, true, false, _workflow_maturin_binar...	1m 37s
Build and test package / build-and-test-binary (windows-latest, 3.10, x86, x86, auto, true, false, _workflow_maturin_binar...	2m 12s
Build and test package / merge-artifacts	4s
Build documentation / Build documentation	18s
	13m 17s

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