Use Messenger::comm() instead of MPI_COMM_WORLD for parallel checkpointing

src/utils/checkpointing/Checkpoint.cpp

@@ -36,7 +36,7 @@ checkpoint()
     create_props.add(HighFive::FileSpaceStrategy(H5F_FSPACE_STRATEGY_FSM_AGGR, true, 0));
 
     HighFive::FileAccessProps fapl;
-    fapl.add(HighFive::MPIOFileAccess{MPI_COMM_WORLD, MPI_INFO_NULL});
+    fapl.add(HighFive::MPIOFileAccess{parallel::Messenger::getInstance().comm(), MPI_INFO_NULL});
     fapl.add(HighFive::MPIOCollectiveMetadata{});
 
     uint64_t& checkpoint_number = ResumingManager::getInstance().checkpointNumber();