Automatically unblock Comm on re-connect

[philippjfr]

Together with holoviz/pyviz_comms#139, this means that the Comm connection is fully re-established when a JupyterLab session is reloaded.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.03%. Comparing base (a22c3b8) to head (2a4a5b1).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7986      +/-   ##
==========================================
- Coverage   87.07%   86.03%   -1.04%     
==========================================
  Files         346      346              
  Lines       53374    53374              
==========================================
- Hits        46476    45921     -555     
- Misses       6898     7453     +555     

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[github-actions]

This pull request has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.