remove duplicated debug printing in CMakeLists.txt for MPI

[StrikerRUS]

find_package(MPI REQUIRED) command prints the same info (even more detailed) as the lines removed in this PR.

...
-- Detecting CXX compile features - done
-- Found MPI_C: /usr/local/Cellar/open-mpi/4.1.1_2/lib/libmpi.dylib (found version "3.1") 
-- Found MPI_CXX: /usr/local/Cellar/open-mpi/4.1.1_2/lib/libmpi.dylib (found version "3.1") 
-- Found MPI: TRUE (found version "3.1")  
-- MPI libraries: /usr/local/Cellar/open-mpi/4.1.1_2/lib/libmpi.dylib
-- MPI C++ libraries: /usr/local/Cellar/open-mpi/4.1.1_2/lib/libmpi.dylib
-- Found OpenMP_C: -fopenmp (found version "4.5") 
-- Found OpenMP_CXX: -fopenmp (found version "4.5") 
-- Found OpenMP: TRUE (found version "4.5")  
-- Performing Test MM_PREFETCH
...

[github-actions]

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