add `uv cache prune` and skip cache for `uv run pytest`

.github/workflows/ci.yaml

@@ -197,7 +197,7 @@ jobs:
           if [[ "${{ github.event_name }}" =~ ^(schedule|workflow_dispatch)$ ]]; then
               slow="--slow"
           fi
-          uv run --resolution lowest-direct pytest $slow --cov=ultralytics/ --cov-report xml tests/
+          uv run --resolution lowest-direct -n pytest $slow --cov=ultralytics/ --cov-report xml tests/
       - name: Upload Coverage Reports to CodeCov
         if: github.repository == 'ultralytics/ultralytics' # && matrix.os == 'ubuntu-latest' && matrix.python-version == '3.11'
         uses: codecov/codecov-action@v5
@@ -205,6 +205,8 @@ jobs:
           flags: Tests
         env:
           CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
+      - name: Prune uv Cache
+        run: uv cache prune --ci
 
   GPU:
     if: github.repository == 'ultralytics/ultralytics' && (github.event_name != 'workflow_dispatch' || github.event.inputs.gpu == 'true')
@@ -225,13 +227,15 @@ jobs:
           if [[ "${{ github.event_name }}" =~ ^(schedule|workflow_dispatch)$ ]]; then
             slow="--slow"
           fi
-          uv run --resolution lowest-direct pytest $slow --cov=ultralytics/ --cov-report xml tests/test_cuda.py
+          uv run --resolution lowest-direct -n pytest $slow --cov=ultralytics/ --cov-report xml tests/test_cuda.py
       - name: Upload Coverage Reports to CodeCov
         uses: codecov/codecov-action@v5
         with:
           flags: GPU
         env:
           CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
+      - name: Prune uv Cache
+        run: uv cache prune --ci
 
   RaspberryPi:
     if: github.repository == 'ultralytics/ultralytics' && (github.event_name == 'schedule' || github.event.inputs.raspberrypi == 'true')