add gh workflow to ensure selftest works (it's part of the release pr…

…ocess)

.github/workflows/python-selftest.yml

@@ -0,0 +1,31 @@
+# This workflow will install Python dependencies, run tests and lint with a single version of Python
+# For more information see: https://help.github.com/actions/language-and-framework-guides/using-python-with-github-actions
+
+name: Selftest
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v4
+    - name: Set up Python 3.10
+      uses: actions/setup-python@v5
+      with:
+        python-version: '3.10'
+        cache: 'pip'
+        cache-dependency-path: setup.py
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        pip install .[selftest]
+    - name: Test with pytest
+      run: |
+        pytest --pyargs cchdo.hydro