github: Run actions on python:3.10-bookworm

This ensures a stable environment for tests even when ubuntu-latest
changes. Also, the dependency on setup-python action has been
removed. That action supports only Ubuntu and limited architectures.

Signed-off-by: Povilas Kanapickas <povilas@radix.lt>

.github/workflows/pylint.yml

@@ -7,12 +7,9 @@ on:
 jobs:
   lint-ruff:
     runs-on: ubuntu-latest
+    container: docker.io/library/python:3.10-bookworm
     steps:
     - uses: actions/checkout@v3
-    - name: Set up Python 3.10
-      uses: actions/setup-python@v5
-      with:
-        python-version: "3.11"
     - name: Analysing the code with ruff
       run: |
         pip install -r test-requirements.txt

.github/workflows/pytest.yml

@@ -12,13 +12,9 @@ on:
 jobs:
   test:
     runs-on: ubuntu-latest
-
+    container: docker.io/library/python:3.10-bookworm
     steps:
     - uses: actions/checkout@v3
-    - name: Set up Python 3.10
-      uses: actions/setup-python@v5
-      with:
-        python-version: "3.10"
     - name: Install dependencies
       run: |
         sudo apt update && sudo apt install -y podman