Add a workflow for making an automatic PyPI release

.github/workflows/pypi-upload.yml

@@ -0,0 +1,47 @@
+name: Upload a new release to PyPI
+
+on:
+  workflow_dispatch:
+  push:
+    branches: [master]
+  release:
+    types: [published]
+
+jobs:
+  build_sdist:
+    name: Build source distribution
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          submodules: recursive
+
+      - name: Build sdist
+        run: pipx run build --sdist
+
+      - name: Upload sdist
+        uses: actions/upload-artifact@v3
+        with:
+          path: dist/*.tar.gz
+
+  upload_pypi:
+    name: Upload to PyPI
+    needs: [build_sdist]
+    runs-on: ubuntu-latest
+    environment: pypi
+    permissions:
+      id-token: write
+    if: github.event_name == 'release' && github.event.action == 'published'
+    steps:
+      - name: Download all dists
+        uses: actions/download-artifact@v3
+        with:
+          # Unpacks default artifact into dist/
+          # If `name: artifact` is omitted, the action will create extra parent dir
+          name: artifact
+          path: dist
+
+      - name: Publish to PyPI
+        uses: pypa/gh-action-pypi-publish@release/v1
+        with:
+          password: ${{ secrets.PYPI_API_TOKEN }}