Do not switch asyncio loop in Jupyter

[philippjfr]

Attempt at fixing #3531

[codecov]

Codecov Report

Merging #3534 (7724261) into master (1efdb60) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #3534   +/-   ##
=======================================
  Coverage   82.85%   82.85%           
=======================================
  Files         199      199           
  Lines       27378    27382    +4     
=======================================
+ Hits        22683    22687    +4     
  Misses       4695     4695           

Impacted Files	Coverage Δ
panel/io/server.py	76.76% <100.00%> (+0.19%)	⬆️

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