websocket: Do not allow a listener or dialer to change TLS while running

[gdamore]

This also covers a few test cases that we were missing.

fixes #

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 81.11%. Comparing base (0058b76) to head (cbe9a27).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1926      +/-   ##
==========================================
+ Coverage   81.00%   81.11%   +0.11%     
==========================================
  Files          94       94              
  Lines       24180    24194      +14     
  Branches     3240     3242       +2     
==========================================
+ Hits        19586    19624      +38     
+ Misses       4522     4497      -25     
- Partials       72       73       +1     

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