Clean-up slightly CMakeLists.txt

Restore the use of HDF5_PREFER_PARALLEL (TRUE)

CMakeLists.txt

@@ -226,6 +226,7 @@ set(PUGS_ENABLE_HDF5 AUTO CACHE STRING
 
 if (PUGS_ENABLE_HDF5 MATCHES "^(AUTO|ON)$")
   # May be risky. (make to show pugs build options)
+  set(HDF5_PREFER_PARALLEL TRUE)
   find_package(HDF5)
   if (HDF5_FOUND)
     # HighFive

tests/CMakeLists.txt

@@ -302,13 +302,3 @@ target_link_libraries (mpi_unit_tests
   ${HIGHFIVE_TARGET}
   stdc++fs
   )
-
-enable_testing()
-
-if(${PUGS_HAS_MPI})
-  set(MPIEXEC_OPTION_FLAGS --oversubscribe)
-  if (NOT "$ENV{GITLAB_CI}" STREQUAL "")
-    set(MPIEXEC_OPTION_FLAGS ${MPIEXEC_OPTION_FLAGS} --allow-run-as-root)
-  endif()
-  set(OptionalCatchTestLauncher ${MPIEXEC} ${MPIEXEC_NUMPROC_FLAG} 3 ${MPIEXEC_OPTION_FLAGS} --path ${PUGS_BINARY_DIR})
-endif()