[3.10] gh-149776: Skip UDP Lite tests if it's not supported (#149777)

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Fix test_socket on Linux kernel 7.1 and newer: skip UDP Lite tests if it's not supported.

(cherry picked from commit 3cfc249)

• Issue: test_socket: BasicUDPLITETest fails on Linux 7.1 and newer #149776

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The Linux kernel of the "AMD64 Fedora Stable" buildbot was upgraded from 7.0 to 7.1, 3 days ago, so test_socket started to fail. The Linux kernel 7.1 removes the UDP Lite support. This PR backports a fix from the main branch.

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cc @hugovk

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Windows (x64): "Build" failed with:

Using "C:\Program Files\Microsoft Visual Studio\2022\Enterprise\MSBuild\Current\Bin\msbuild.exe" (found in the Visual Studio installation)
Installing Python via nuget...
The system cannot execute the specified program.
Cannot locate python.exe on PATH or as PYTHON variable Error: Process completed with exit code 1.

I tried to build Python 3.11 on my Windows 11 VM. The externals\nuget.exe program is corrupted. When I tried to run it manually, I get a popup saying that the file is damaged or cannot be read.

The program is downloaded by the following command from PCbuild/find_python.bat:

powershell.exe -Command Invoke-WebRequest https://aka.ms/nugetclidl -OutFile 'C:\victor\python\3.10\PCbuild\\..\externals\nuget.exe'

It seems like the nuget download URL is outdated. The URL was updated... yesterday by commit 106eb53. I backported this change as well.

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macOS: Oh, test_ssl failed with issue gh-151504:

======================================================================
ERROR: test_load_verify_cadata (test.test_ssl.ContextTests)
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Traceback (most recent call last):
File "/Users/runner/work/cpython/cpython/Lib/test/test_ssl.py", line 1509, in test_load_verify_cadata
ctx.load_verify_locations(cadata=cacert_der)
ssl.SSLError: [ASN1: NOT_ENOUGH_DATA] not enough data (_ssl.c:4040)
======================================================================
ERROR: test_connect_cadata (test.test_ssl.SimpleBackgroundTests)
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Traceback (most recent call last):
File "/Users/runner/work/cpython/cpython/Lib/test/test_ssl.py", line 2152, in test_connect_cadata
ctx.load_verify_locations(cadata=der)
ssl.SSLError: [ASN1: NOT_ENOUGH_DATA] not enough data (_ssl.c:4040)

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macOS: Oh, test_ssl failed with issue gh-151504:

It lacks the ssl fix backport: #153312.