Build wheel in CI, upload artifact for perusal

Signed-off-by: Aarni Koskela <akx@iki.fi>

.github/workflows/ci.yml

@@ -18,6 +18,19 @@ jobs:
             - name: Run ruff
               run: ruff docker tests
 
+    build:
+      runs-on: ubuntu-22.04
+      steps:
+        - uses: actions/checkout@v4
+        - uses: actions/setup-python@v4
+          with:
+            python-version: '3.x'
+        - run: pip3 install build && python -m build .
+        - uses: actions/upload-artifact@v4
+          with:
+            name: dist
+            path: dist
+
     unit-tests:
         runs-on: ubuntu-latest
         strategy: