Published sdist (12.0.0) cannot be installed from source — it omits the VERSION file; sdists built from HEAD are fine

[sethc555]

Installing hubspot-api-client from source fails:

$ docker run --rm python:3.12 pip install --no-binary :all: hubspot-api-client
...
FileNotFoundError: [Errno 2] No such file or directory: 'VERSION'

The published 12.0.0 sdist does not contain the VERSION file setup.py reads — but an sdist built from current HEAD includes it and installs cleanly (verified). A release built the normal way should fix it; no code change needed.

Found while build-checking popular PyPI packages for source-install breakage (wheelproof); claims verified twice in clean python:3.12 containers.