Ignores CryptographyDeprecationWarning

[bobokun]

We're seeing these warnings happen when running tronctl after upgrading twisted. This is due to twisted upstream library and is safe to ignore. Ideally we can remove this workaround once it's removed in twisted.

❯ tronctl -h
/opt/venvs/tron/lib/python3.8/site-packages/twisted/conch/ssh/transport.py:97: CryptographyDeprecationWarning: Blowfish has been deprecated
  b”blowfish-cbc”: (algorithms.Blowfish, 16, modes.CBC),
/opt/venvs/tron/lib/python3.8/site-packages/twisted/conch/ssh/transport.py:101: CryptographyDeprecationWarning: CAST5 has been deprecated
  b”cast128-cbc”: (algorithms.CAST5, 16, modes.CBC),
/opt/venvs/tron/lib/python3.8/site-packages/twisted/conch/ssh/transport.py:106: CryptographyDeprecationWarning: Blowfish has been deprecated
  b”blowfish-ctr”: (algorithms.Blowfish, 16, modes.CTR),
/opt/venvs/tron/lib/python3.8/site-packages/twisted/conch/ssh/transport.py:107: CryptographyDeprecationWarning: CAST5 has been deprecated
  b”cast128-ctr”: (algorithms.CAST5, 16, modes.CTR),
usage: tronctl [-h] [--version] [-v] [--server SERVER] [--cluster_name CLUSTER_NAME] [-s]
               {start,rerun,retry,recover,cancel,backfill,disable,enable,fail,success,skip,skip-and-publish,stop,kill,move,publish,discard,version} ...

[nemacysts]

lgtm assuming that the requirements files are correct - i have some suggestions for rewording/adding comments, but they're not necessarily blocking