Remove matrix setup for CI

.github/workflows/tests.yaml

@@ -7,10 +7,6 @@ on:
 jobs:
   tests:
     runs-on: ubuntu-latest
-    strategy:
-      max-parallel: 4
-      matrix:
-        python-version: "3.11"
 
     services:
       postgres:
@@ -24,19 +20,15 @@ jobs:
         options: --health-cmd pg_isready --health-interval 5s --health-timeout 5s --health-retries 5
 
     steps:
-    - uses: actions/checkout@v2
-
-    - name: Setup Python
-      uses: actions/setup-python@v2
+    - uses: actions/checkout@v4
+    - name: Install poetry
+      run: pipx install poetry
+    - uses: actions/setup-python@v5
       with:
-        python-version: "3.11"
         cache: 'poetry'
-        cache-dependency-path: 'poetry.lock'
 
     - name: Install dependencies
-      run: |
-        python -m pip install poetry
-        poetry install
+      run: poetry install
 
     - name: Run tests
       env:
@@ -45,4 +37,4 @@ jobs:
         DB_USER: postgres
         DB_PASS: postgres
         DB_BASE: db_test
-      run: cd app && pytest .
+      run: cd app && poetry run pytest