Remove ParallelMPI Python tests

The auto-converted ParallelMPI Python tests will be converted
to C++ so remove the non-working Python script.

Change-Id: I0ed91362ced9297769696b8981601a097a8bc3d6
Merge topic 'remove-parallel-mpi-python-tests' into master

0b9b4e1e Remove ParallelMPI Python tests