Handle --ico-path CLI argument

[philippjfr]

bokeh serve CLI allows setting an --ico-path to control the favicon. Since we perform our own handling of favicons this option was ignored. We now hook into the mechanism.

[codecov]

Codecov Report

Attention: Patch coverage is 94.44444% with 3 lines in your changes missing coverage. Please review.

Project coverage is 86.04%. Comparing base (0bb1ccc) to head (119ce21).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
panel/template/base.py	80.00%	2 Missing ⚠️
panel/command/serve.py	80.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7992      +/-   ##
==========================================
- Coverage   87.07%   86.04%   -1.04%     
==========================================
  Files         346      346              
  Lines       53374    53460      +86     
==========================================
- Hits        46478    45997     -481     
- Misses       6896     7463     +567     

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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.