Bump to CPython 3.14.0a5

[zanieb]

No description provided.

[zanieb]

Windows x86-64 failed with

cpython>      3>C:\Users\runneradmin\AppData\Local\Temp\python-build-o24wgyzl\Python-3.14.0a5\Python\ceval.c(791): fatal error C1001: Internal compiler error. [C:\Users\RUNNER~1\AppData\Local\Temp\python-build-o24wgyzl\Python-3.14.0a5\PCbuild\pythoncore.vcxproj]
cpython>          (compiler file 'D:\a\_work\1\s\src\vctools\Compiler\Utc\src\p2\main.cpp', line 253)
cpython>           To work around this problem, try simplifying or changing the program near the locations listed above.
cpython>          If possible please provide a repro here: https://developercommunity.visualstudio.com/
cpython>          Please choose the Technical Support command on the Visual C++
cpython>           Help menu, or open the Technical Support help file for more information
cpython>            link!InvokeCompilerPass()+0xdab22
cpython>            link!InvokeCompilerPass()+0xdab22
cpython>            link!InvokeCompilerPass()+0xda884
cpython>            link!InvokeCompilerPass()+0xd76f7
cpython>            link!InvokeCompilerPass()+0xd75fc
cpython>            link!InvokeCompilerPassW()+0xf25bd

Hopefully spurious.

[Fidget-Spinner]

@zanieb I don't think it's spurious :(. We had to fix this upstream as well python/cpython#130009.

[zanieb]

Oh thanks! That will save me a lot of time.

[Fidget-Spinner]

Relevant original PR that modified the build script for Windows python/cpython#130005