Flake8 reports wrong severity level for code Fxxx

Flake8 reports wrong severity level for code Fxxx: a task in MiMo-V2.6-RL-harbor-code: MiMo-V2.6-RL Code (Harbor) (Harbor dataset). Currently, these error codes are reported with the Warning severity level by Flake8 plugin instead of Error level, same issue as…

The task

Currently, these error codes are reported with the **Warning** severity level by Flake8 plugin instead of **Error** level, same issue as https://github.com/python-lsp/python-lsp-server/issues/220 for E999 code.

Part of FineEnvs/MiMo-V2.6-RL-harbor-code.