[ci] Temp: install openwisp-utils

Author: pandafy

.github/workflows/ci.yml

@@ -70,6 +70,8 @@ jobs:
           pip install -U pip wheel setuptools
           pip install -U -r requirements-test.txt
           pip install -U -e .
+          # TODO: Remove before merging
+          pip install -UI --force-reinstall --no-cache-dir --no-deps "openwisp-utils @ https://github.com/openwisp/openwisp-utils/archive/refs/heads/issues/633-ValidatedModelSerializer.tar.gz
           pip install ${{ matrix.django-version }}
 
       - name: Start redis