Upgrade 3.14 binary to 3.14.0

[jb3]

Originally introduced in commits c7fae91 and
b7e0aec.

These commits failed in CI as the tests that are run when pyenv has built a Python
binary failed:

 > [builder-py-3_14 1/1] RUN /build_python.sh 3.14.0:
996.0 
996.0 FAILED (failures=3, skipped=10)
996.0 test test_xml_etree_c failed
996.0 0:02:06 load avg: 3.06 [43/43] test_xml_etree_c failed (3 failures)
996.0 
996.0 Total duration: 2 min 6 sec
996.0 Total tests: run=9,295 failures=6 skipped=314
996.0 Total test files: run=43/43 failed=2 skipped=1
996.0 Result: FAILURE
996.0 make: *** [Makefile:1019: profile-run-stamp] Error 2
------
ERROR: failed to build: failed to solve: process "/bin/sh -c /build_python.sh 3.14.0" did not complete successfully: exit code: 1

I'm not sure entirely what about the way we build here caused that, and don't
think this is explicitly caused by any flags that we are setting (or amending
from defaults).

[jb3]

Actually, looking at python/cpython#128838 there is a
chance this is coming from the fact we add --with-system-expat.

I'm not 100% sure why we add that flag currently or what changed between the
release candidate and 3.14.0 that would cause this to suddenly cause problems?

[MarkKoz]

It was probably copied from the build arguments in the official Python Docker image.

I think it's okay to remove if it's causing us trouble.