⬆️ Bump websocket-client to version 1.5.3 to 1.6.1

[QuinnDamerell]

• Your changes are not possible to do through a plugin and relevant
  to a large audience (ideally all users of OctoPrint)
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What does this PR do and why is it necessary?

Bumps the WebSocket lib used to 1.6.1, which fixes a bad dead lock in the lib but is still compatible with PY 3.7.

How was it tested? How can it be tested by the reviewer?

I built OctoPrint and it ran with no problem.

Any background context you want to provide?

From our discussion in #4957

What are the relevant tickets if any?

Screenshots (if appropriate)

Further notes

[foosel]

Closing this as it got superseded by 8a9478c against staging/maintenance for 1.10.0rc3.