Unable to build any Python packages with own oneAPI installation on Narwhal (Cray)

[climbfuji]

Describe the bug
PR #1318 adds basic support for oneAPI 2024.2.1 on Narwhal. This uses our own oneAPI installation instead of an official Cray installation. There must be several environment variables and hooks missing, since I am unable to build any Python packages (Python itself builds fine in spack-stack, but any pip installation attempt fails with a segfault).

To Reproduce
Requires access to Narwhal, but then try to build the unified environment (or the NEPTUNE standalone environment with +python) with oneAPI.

Expected behavior
Python packages can be installed.

System:
Narwhal

Additional context

Navy DSRC admins are going to install and configure oneAPI 2024.2.0 or 2024.2.1 on Narwhal in the next month. We should switch over to this version of oneAPI once that is complete.