The current version is causing debci test failure since it is emitting
a warning to stderr:
https://ci.debian.net/packages/o/openmpi/unstable/amd64/76038487/

515s --------------------------------------------------------------------------
515s A deprecated MCA variable value was specified in the environment or
515s on the command line.  Deprecated MCA variables should be avoided;
515s they may disappear in future releases.
515s
515s   Deprecated variable: schizo_proxy
515s   New variable:        personality
515s --------------------------------------------------------------------------

This causes openmpi's own debci tests to fail.
It also affects all other packages using openmpi.

The problem can be seen in mpi4py tests at
https://ci.debian.net/data/autopkgtest/unstable/amd64/m/mpi4py/75910556/log.gz
mpi4py is only passing debci circumstantially since it happens to be
using Restrictions: allow-stderr in debian/tests/control

But this is not a good solution in general.  Packages without
allow-stderr are failing because of the warning message,
including scifem, netgen, and openmpi itself.

The message says schizo_proxy is being set in the environment, but the
client packages are not setting it explicitly. It must be in the
openmpi configuration. Wherever the variable is being set, can it be
updated, to save the sanity of all the client packages?