Add step to minimize uv cache in CI workflow (#713)

Author: bhimrazy

.github/workflows/ci-testing.yml

@@ -75,6 +75,9 @@ jobs:
           name: codecov-umbrella
           fail_ci_if_error: false
 
+      - name: Minimize uv cache
+        run: uv cache prune --ci
+
   testing-guardian:
     runs-on: ubuntu-latest
     needs: pytester