ci: add semantic-release to publish to PyPI

.github/workflows/release.yml

@@ -0,0 +1,29 @@
+name: Release
+on: [push]
+
+jobs:
+  release:
+    runs-on: ubuntu-latest
+    environment:
+      name: pypi
+      url: https://pypi.org/p/iati-sphinx-theme
+    permissions:
+      contents: write
+      id-token: write
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
+        with:
+          python-version: "3.10"
+      - uses: actions/setup-node@v4
+        with:
+          node-version: "20.x"
+      - name: Install dependencies
+        run: npm ci
+      - name: Build CSS
+        run: npm run build
+      - name: Release
+        run: npx semantic-release --dry-run --branches publish-pypi
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          PYPI_TOKEN: ${{ secrets.PYPI_TOKEN }}

iati_sphinx_theme/__init__.py

@@ -4,7 +4,7 @@
 
 import sphinx.application
 
-__version__ = "0.0.0"
+__version__ = "0.0.0-semantically-released"
 
 
 def setup(app: sphinx.application.Sphinx) -> None: