new name

Co-authored-by: James Dark <65899899+jhdark@users.noreply.github.com>

Author: RemDelaporteMathurin

test/system_tests/test_io.py

@@ -4,7 +4,7 @@
 import mpi4py.MPI as MPI
 
 
-def test_out_in():
+def test_writing_and_reading_of_species_function_using_checkpoints():
     """
     Tests that a model can write a checkpoint file and another model can read it.
     """