remove OpenMPI, which has been rebuilt in EESSI#488

Author: bedroge

easystacks/software.eessi.io/2023.06/eessi-2023.06-eb-4.8.2-2023a.yml

@@ -55,8 +55,4 @@ easyconfigs:
   - gnuplot-5.4.8-GCCcore-12.3.0.eb: 
       options:
         from-pr: 19261
-  - OpenMPI-4.1.5-GCC-12.3.0.eb:
-      options:
-        from-pr: 19940
-        rebuild: True
   - OpenFOAM-10-foss-2023a.eb