Fix CI pipeline failures: remove pip cache from setup-python, add missing env vars

- Remove 'cache: pip' from setup-python in lint, typecheck, test jobs to fix
  intermittent 'archive/tar: write too long' errors on act_runner pods
- Add CARTSNITCH_SERVICE_KEY and CARTSNITCH_FERNET_KEY to test job env
  to satisfy Settings pydantic model requirements

Co-Authored-By: Paperclip <noreply@paperclip.ing>

.gitea/workflows/ci.yml

@@ -26,7 +26,6 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: "3.12"
-          cache: pip
       - run: pip install ruff
       - name: Ruff lint
         run: ruff check .
@@ -41,7 +40,6 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: "3.12"
-          cache: pip
       - name: Install system dependencies
         run: sudo apt-get update && sudo apt-get install -y libpq-dev build-essential
       - run: pip install -e ".[dev]" mypy
@@ -83,12 +81,13 @@ jobs:
       CARTSNITCH_DATABASE_URL: postgresql+asyncpg://cartsnitch:cartsnitch_test@localhost:5432/cartsnitch_test
       CARTSNITCH_REDIS_URL: redis://localhost:6379/0
       CARTSNITCH_JWT_SECRET_KEY: test-secret-do-not-use-in-prod
+      CARTSNITCH_SERVICE_KEY: test-service-key-do-not-use-in-prod
+      CARTSNITCH_FERNET_KEY: wXWQsC0FZlhSz2t_tfVQjNUSP8vgAGG3o3pkjrX8Bw0=
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-python@v5
         with:
           python-version: "3.12"
-          cache: pip
       - name: Install system dependencies
         run: sudo apt-get update && sudo apt-get install -y libpq-dev build-essential
       - run: pip install -e ".[dev]"