Fix file name

Author: yaph

.github/workflows/pythonpackage.yml

@@ -23,7 +23,7 @@ jobs:
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
-        pip install -r requirements_dev.txt
+        pip install -r requirements-dev.txt
     - name: Test with pytest
       run: |
         pytest