Add Python 3.15 socket SSL and platform updates

[JelleZijlstra]

Summary:

• Add Python 3.15 Linux CAN ISO-TP socket constants.
• Add Python 3.15 SSL signature algorithm, group, ciphersuite, and TLS 1.3 PSK APIs.
• Add small Python 3.15 platform/runtime updates for hashlib, mmap, platform, and resource.
• Remove or narrow the matching 3.15 stubtest allowlist entries.

Relevant report entries:

• Added Linux CAN ISO-TP socket constants (CPython PR: Expose ISO-TP Contants for Linux >= 5.10 cpython#86819; source: https://github.com/python/cpython/blob/main/Modules/socketmodule.c)
• Added SSL TLS 1.3 PSK support, signature algorithm APIs, and group/ciphersuite APIs (CPython PRs: gh-133623: Add ssl.HAS_PSK_TLS13 to detect external TLS 1.3 PSK support cpython#133624, Add support in SSL module for getting/setting groups used for key agreement cpython#136306, Add support in SSL module for getting/setting TLS 1.3 cipher suites cpython#137197, Add support in SSL module for getting and setting TLS signature algorithms cpython#138252; source: https://github.com/python/cpython/blob/main/Lib/ssl.py)
• Added hashlib.scrypt to hashlib.__all__ for Python 3.15 (CPython source: https://github.com/python/cpython/blob/e81025e6d2e01e38c5a5b656af5739ac9df5ff55/Lib/hashlib.py)
• Added mmap.mmap(trackfd=...) on Windows, mmap.mmap.flush(flags=...), mmap.mmap.set_name(), and 3.15 optional None bounds for find(), rfind(), and madvise(); removed mmap.mmap.resize() on Darwin (source: https://github.com/python/cpython/blob/main/Modules/mmapmodule.c)
• Added resource constants RLIMIT_NTHR, RLIMIT_UMTXP, RLIMIT_THREADS, RLIM_SAVED_CUR, and RLIM_SAVED_MAX (CPython PR: Add more RLIMIT_* constants cpython#137512; source: https://github.com/python/cpython/blob/main/Modules/resource.c)
• Removed platform.java_ver for 3.15 (source: https://github.com/python/cpython/blob/main/Lib/platform.py)

[JelleZijlstra]

weird

[JelleZijlstra]

Apparently this is correct: python/cpython#138276. It used to be available on all platforms (but it would fail on platforms without MREMAP), now it only exists if it works.

[hauntsaninja]

do these definitely need the ()? magic trick?

[JelleZijlstra]

Not really, I cleaned up a bunch more socket constants that should have been added.

[github-actions]

According to mypy_primer, this change has no effect on the checked open source code. 🤖🎉

[srittau]

i'm on mobile right now, so I can't select multiple rows, but can we fix the version_info check to use the standard format?