fix: improved build process.

.github/workflows/python-package.yml

@@ -19,12 +19,10 @@ jobs:
       uses: actions/setup-python@v4
       with:
         python-version: ${{ matrix.python-version }}
-    - name: Install dependencies
+    - name: Install build environment
       run: |
         python -m pip install --upgrade pip
         python -m pip install tox setuptools pytest pytest-cov codecov
-        if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
-        poetry install
-    - name: Lint with tox
+    - name: Build and test with tox.
       run: |
         tox