Create Python workflow for GitHub Actions (#1)

* Create Python workflow for GitHub Actions

In case we receive PRs via GitHub, it would be good if we have a basic setup for running lints and tests, even if we cannot execute the full pipeline. We might migrate our pipeline here in the future.

* Update Poetry lock

.github/workflows/python.yml

@@ -0,0 +1,32 @@
+# This workflow will install Python dependencies, run tests and lint with a single version of Python
+# For more information see: https://docs.github.com/en/actions/automating-builds-and-tests/building-and-testing-python
+
+name: NaC Python SDK
+
+on:
+  push
+
+permissions:
+  contents: read
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v4
+    - name: Set up Python 3.9
+      uses: actions/setup-python@v3
+      with:
+        python-version: "3.9"
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        pip install poetry
+        poetry install
+    - name: Lint with pylint
+      run: |
+        poetry run pylint network_as_code
+    - name: Test with pytest
+      run: |
+        poetry run pytest