ci: Change how poetry deps are cached (#310)

.github/workflows/test_tap.yml

@@ -57,27 +57,22 @@ jobs:
         # file in the cache. See issue #119
         key: api-cache-v4-${{ steps.get-date.outputs.date }}
 
-    - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v5
-      with:
-        python-version: ${{ matrix.python-version }}
     - name: Install Poetry
       uses: snok/install-poetry@v1
       with:
         # Version of Poetry to use
         version: 1.8.3
         virtualenvs-create: true
         virtualenvs-in-project: true
-    - name: Load cached venv
-      id: cached-poetry-dependencies
-      uses: actions/cache@v4
+    - name: Set up Python ${{ matrix.python-version }}
+      uses: actions/setup-python@v5
       with:
-        path: .venv
-        key: venv-4-${{ runner.os }}-${{ hashFiles('**/poetry.lock') }}-${{ matrix.python-version }}
+        python-version: ${{ matrix.python-version }}
+        cache: poetry
     - name: Install dependencies
       run: |
+        poetry env use ${{ matrix.python-version }}
         poetry install
-      if: steps.cached-poetry-dependencies.outputs.cache-hit != 'true'
     - name: Test with pytest
       id: test_pytest
       continue-on-error: true