add mongo service in github actions

jobs:

  test:

    runs-on: ubuntu-latest

    services:

      mongodb:

        image: mongo:6.0

        env:

          MONGO_INITDB_ROOT_USERNAME: test_admin

          MONGO_INITDB_ROOT_PASSWORD: test_password

        ports:

          - 27017:27017

    timeout-minutes: 10

    strategy:

      matrix:

        run: pip install tox

      - name: Run tox for python 3.12 - tests only

        env:

          MONGO_URI: "mongodb://test_admin:test_password@localhost:27017/test_db?authSource=admin"

        run: tox -e 3.12