chore(deps): update dependency protobuf to v6 [security]

Author: renovate[bot]

auto_server/requirements.txt

@@ -5,7 +5,7 @@ immutabledict==4.2.0
 numpy==2.1.1
 ortools==9.10.4067
 pandas==2.2.2
-protobuf==5.27.2
+protobuf==6.33.5
 python-dateutil==2.9.0.post0
 pytz==2025.2
 six==1.16.0