git config wrote core.autocrlf into the repository git init creates in the
extracted CPython source. Nothing outside deps/build reads that repository, so
the setting was already contained.
-c applies the override to the one invocation instead, so no repository config is
written at all. It cannot reuse PATCH_CMD, so the shared flags are spelled out here.
git apply inherits the caller's configuration, so under core.autocrlf=input it
rewrites the patched PCbuild/find_python.bat to LF. cmd.exe cannot resolve goto
labels in an LF batch file, so CPython's build fails with "The system cannot
find the batch label specified - begin_search" and then "Cannot locate
python.exe on PATH or as PYTHON variable".
git init already runs in the extracted source, so setting core.autocrlf on the
repository it creates is enough, without touching the shared PATCH_CMD.