install R for test run

Author: kgoebler

.github/workflows/test_package.yml

@@ -22,6 +22,10 @@ jobs:
       uses: actions/setup-python@v3
       with:
         python-version: ${{ matrix.python-version }}
+    - name: Set up R
+      uses: r-lib/actions/setup-r@v2
+      with:
+        r-version: '4.3.2'
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip