Add C version to test crash

Author: oscarbenjamin

.github/workflows/buildwheel.yml

@@ -268,6 +268,8 @@ jobs:
       - run: bin/install_latest_flint_ubuntu.sh
       - run: pip install --upgrade pip
       - run: pip install -r requirements-dev.txt
+      - run: gcc test.c -l flint -o test.exe
+      - run: ./test.exe
       - run: spin run python test.py
       - run: spin run -- pytest --doctest-glob='*.rst' doc/source
       - run: spin docs