chore: Update pip installation commands in pre-release workflow

.github/workflows/pre-release.yml

@@ -65,11 +65,11 @@ jobs:
       - name: Test CLI
         run: |
           if [ "${{ inputs.release_type }}" == "base" ]; then
-            pip install src/backend/base/dist/*.whl
+            python -m pip install src/backend/base/dist/*.whl
           else
-            pip install dist/*.whl
+            python -m pip install dist/*.whl
           fi
-          langflow run --host 127.0.0.1 --port 7860 &
+          python -m langflow run --host 127.0.0.1 --port 7860 &
           SERVER_PID=$!
           # Wait for the server to start
           timeout 40 bash -c 'until curl -f http://127.0.0.1:7860/health; do sleep 1; done' || (echo "Server did not start in time" && kill $SERVER_PID && exit 1)