Move test requirements to file

Author: antonmyronyuk

.github/workflows/tests.yaml

@@ -21,7 +21,7 @@ jobs:
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip setuptools
-          pip install pytest
+          pip install -r requirements/test.txt
 
       - name: Tests with pytest
         run: pytest

requirements/test.txt

@@ -0,0 +1 @@
+pytest