fix: packages: mpi: require: openmpi

Author: wdconinc

spack-environment/packages.yaml

@@ -264,6 +264,9 @@ packages:
   mosquitto:
     require:
     - '@2.0.18:'
+  mpi:
+    require:
+    - openmpi
   nlohmann-json:
     require:
     - '@3.11.2:'