gh-152709: Update ssl docs for OpenSSL 4

[ishaanlabs-gg]

gh-152709 updates the SSL module documentation for OpenSSL 4:

• avoids listing legacy version-specific protocol constants in the ssl module pydoc as generally available
• documents that PROTOCOL_SSLv3, PROTOCOL_TLSv1, PROTOCOL_TLSv1_1, and PROTOCOL_TLSv1_2 are unavailable with OpenSSL 4.0 or later
• updates the hostname-checking example to use PROTOCOL_TLS_CLIENT instead of the version-specific PROTOCOL_TLSv1_2

Validation:

• git diff --check
• Attempted make -C Doc venv, but local validation could not complete because the macOS system Python failed while importing site during venv creation with a UnicodeDecodeError before Sphinx/blurb could be installed.

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[python-cla-bot]

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[read-the-docs-community]

Documentation build overview

📚 cpython-previews | 🛠️ Build #33382292 | 📁 Comparing b88fed4 against main (a5be0d8)

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2 files changed

± library/ssl.html
± whatsnew/changelog.html