ci: Add Python package workflow

This commit adds a GitHub Actions CI workflow that builds source and
built distribution (wheel) packages.

Signed-off-by: Stephanos Ioannidis <root@stephanos.io>

.github/workflows/package.yml

@@ -0,0 +1,55 @@
+name: Package
+
+on:
+  push:
+    branches:
+    - main
+    - v*-branch
+  pull_request:
+    branches:
+    - main
+    - v*-branch
+  workflow_call:
+
+concurrency:
+  group: ${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  package:
+    name: Package
+    runs-on: ubuntu-22.04
+
+    steps:
+    - name: Set up Python
+      uses: actions/setup-python@v5
+      with:
+        python-version: '3.10'
+
+    - name: Check Python version
+      run: |
+        set -x
+        python --version
+        pip --version
+        python -c "import platform; print(platform.architecture())"
+
+    - name: Install Python dependencies
+      run: |
+        pip install --user setuptools wheel
+
+    - name: Check out Kconfiglib source code
+      uses: actions/checkout@v4
+
+    - name: Build source distribution
+      run: |
+        python setup.py sdist
+
+    - name: Build built distribution wheel
+      run: |
+        python setup.py bdist_wheel
+
+    - name: Upload artifacts
+      uses: actions/upload-artifact@v4
+      with:
+        name: dist
+        path: dist/*