gh-96954: Fix make regen-unicodedata in out-of-tree builds

[hroncok]

This avoids:

python3.13 Tools/unicode/makeunicodedata.py
python3.13: can't open file '.../build/debug/Tools/unicode/makeunicodedata.py': [Errno 2] No such file or directory
make: *** [Makefile:1498: regen-unicodedata] Error 2

• Issue: Port PyPy's new unicode name db format to optimize binary CPython size #96954

[vstinner]

I confirm that the fix works as expected, there is no error:

git pr 112118

git clean -fdx
mkdir WORKDIR
cd WORKDIR
../configure --with-pydebug
make regen-all
make regen-unicodedata

I also tested that other regen commands don't fail:

make regen-stdlib-module-names
make regen-limited-abi
make regen-configure

[vstinner]

Please run make regen-unicodedata in the source directory and include changes of generated files in your PR. See: https://github.com/python/cpython/actions/runs/6879727597/job/18712327275?pr=112118

[hroncok]

There's a typo in the second commit message. I know you don't like force pushing to PRs, so please correct it when squashing.

[hroncok]

Thanks.

[vstinner]

Thanks for your fix! We test out-of-free build in the CI, but we don't run make regen-all in this out-of-tree CI job. make regen-all is tested in a CI job which don't build Python out-of-tree.