Bump to PyO3 0.23.3, avoiding 0.23.x's previous soundness issues. #1022

Job	Run time
list	17s
test (tests-3.9)	56s
test (tests-3.10)	56s
test (tests-pypy3.10)	1m 55s
test (tests-3.11)	1m 1s
test (tests-3.12)	1m 5s
test (tests-3.13)	1m 48s
test (tests-3.13t)	1m 2s
test (audit)	1m 31s
test (build)	1m 24s
test (style)	1m 7s
test (typing)	2m 7s
test (docs(dirhtml))	1m 29s
test (docs(doctest))	1m 46s
test (docs(linkcheck))	2m 7s
test (docs(man))	1m 19s
test (docs(spelling))	1m 21s
test (docs(style))	2m 37s
manylinux (x86_64)	2m 38s
musllinux (aarch64-unknown-linux-musl)	2m 37s
macos (x86_64)	3m 51s
musllinux (i686-unknown-linux-musl)	2m 29s
macos (aarch64)	3m 43s
sdist	50s
musllinux (x86_64-unknown-linux-musl)	2m 16s
manylinux (x86)	4m 4s
manylinux (aarch64)	2m 56s
windows-free-threaded (x64)	3m 19s
manylinux (armv7)	3m 11s
windows (x64)	5m 16s
manylinux (s390x)	2m 53s
windows (x86)	4m 30s
windows-free-threaded (x86)	4m 12s
manylinux (ppc64le)	2m 48s
release	1m 33s
	1h 18m 54s

Provide feedback