🧪 Set the cache key prefix in CI

Author: webknjaz

.github/workflows/self-smoke-test-action.yml

@@ -259,6 +259,7 @@ jobs:
 
     uses: tox-dev/workflow/.github/workflows/reusable-tox.yml@617ca35caa695c572377861016677905e58a328c  # yamllint disable-line rule:line-length
     with:
+      cache-key-for-dependency-files: ''
       check-name: >-
         🧪 🐍${{
           matrix.python-version