try without matrix

.github/workflows/gdal.yml

@@ -70,11 +70,8 @@ jobs:
           poetry run python -m pip install -U setuptools wheel
           poetry run python -m pip install --no-build-isolation --no-cache-dir --force-reinstall gdal==$(gdal-config --version)
       - uses: r-lib/actions/setup-r@v2
-        # r-lib/actions/setup-r@v2 is supposed to install version ${{ matrix.R }}, BUT, it doesn't.
-        # When asking for 4.1.2 - it's installing a new version! Or at least reporting a newer
-        # version.
         with:
-          r-version: ${{ matrix.R }}
+          r-version: "4.1.2"
       - name: Cache /home/runner/work/_temp/Library
         # When installing cffdrs, a bunch of stuff is downloaded and compiled and placed in
         # /home/runner/work/_temp/Library ; By caching this folder, subsequent calls to