telnetlib deprecation breaks self tests.

[petersilva]

when running pytest tests we get deprecation warnings:

sarracenia/flowcb/work/send_egc_les.py:32
  /home/peter/Sarracenia/sr3/sarracenia/flowcb/work/send_egc_les.py:32: DeprecationWarning: 'telnetlib' is deprecated and slated for removal in Python 3.13
    import logging, telnetlib, sys, os, stat, time

Presumably someone needs to re-write these tests with plain sockets... or research something else... because telnetlib is going away.

All we can do for now is disable the test.

[reidsunderland]

I think we can delete that plugin. We're currently using the Sundew version and will eventually replace it with an sr3 feed using the SafetyNET II RESTful API: https://www.inmarsat.com/content/dam/inmarsat/corporate/documents/maritime/solutions-services/Inmarsat_ECG%20API%20Manual_V3.0.pdf.downloadasset.pdf