Update action.yml to add shell

Author: mcbarton

.github/actions/Build_and_Test_CppInterOp/action.yml

@@ -6,6 +6,7 @@ runs:
   steps:
     - name: Build and Test/Install CppInterOp
       if: runner.os != 'Windows'
+      shell: bash
       run: |
         LLVM_DIR="$(pwd)/llvm-project"
         LLVM_BUILD_DIR="$(pwd)/llvm-project/build"
@@ -67,6 +68,7 @@ runs:
 
     - name: Build and Test/Install CppInterOp on Windows systems
       if: runner.os == 'Windows'
+      shell: powershell
       run: |
         $env:PWD_DIR= $PWD.Path
 
@@ -131,4 +133,4 @@ runs:
                 -DClang_DIR="$env:LLVM_BUILD_DIR\lib\cmake\clang"  -DCODE_COVERAGE=${{ env.CODE_COVERAGE }}  -DCMAKE_INSTALL_PREFIX="$env:CPPINTEROP_DIR"  ..\
                 cmake --build . --config ${{ env.BUILD_TYPE }} --target googletest --parallel ${{ env.ncpus }}
         }
-        cmake --build . --config ${{ env.BUILD_TYPE }} --target check-cppinterop --parallel ${{ env.ncpus }}
+        cmake --build . --config ${{ env.BUILD_TYPE }} --target check-cppinterop --parallel ${{ env.ncpus }}