Fix bento warning

[linkous8]

Bento Output:

hadolint DL3013 https://github.com/hadolint/hadolint/wiki/DL3013
     > Dockerfile:6
     ╷
    6│   RUN pip3 install PyYAML redis requests pandas
     ╵
     = Pin versions in pip. Instead of `pip install <package>` use `pip install
       <package>==<version>`