Add openmpi install to CI (#551)

This PR adds to the CCPP Prebuild CI test to install open-mpi v4.1.6, which is now a requirement for CCPP.

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Co-authored-by: dustinswales <dswales@ucar.edu>

.github/workflows/prebuild.yaml

@@ -31,6 +31,17 @@ jobs:
         python -m pip install --upgrade pip
         pip install flake8 pytest
         if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
+    - name: Install open mpi
+      run: |
+        wget https://github.com/open-mpi/ompi/archive/refs/tags/v4.1.6.tar.gz
+        tar -xvf v4.1.6.tar.gz
+        cd ompi-4.1.6
+        ./autogen.pl
+        ./configure --prefix=/home/runner/ompi-4.1.6
+        make -j4
+        make install
+        echo "LD_LIBRARY_PATH=/home/runner/ompi-4.1.6/lib:$LD_LIBRARY_PATH" >> $GITHUB_ENV
+        echo "PATH=/home/runner/ompi-4.1.6/bin:$PATH" >> $GITHUB_ENV
     - name: ccpp-prebuild unit tests
       run: |
         export PYTHONPATH=$(pwd)/scripts:$(pwd)/scripts/parse_tools