compat: Bokeh upper pin policy

[hoxbro]

It is a pain to have a tight upper pin for Bokeh. This means we always need a release after a new Bokeh (and Panel) release.

Most of the code runs successfully without the custom models in GeoViews. So, this PR will add a warning if we are outside the range of the Bokeh version specified by the build-system and remove the upper pin.

[codecov]

Codecov Report

Attention: Patch coverage is 77.14286% with 8 lines in your changes missing coverage. Please review.

Project coverage is 69.82%. Comparing base (b0618a3) to head (2bef9a1).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
geoviews/models/custom_tools.py	68.18%	7 Missing ⚠️
geoviews/tests/plotting/bokeh/test_models.py	92.30%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #776      +/-   ##
==========================================
+ Coverage   69.36%   69.82%   +0.46%     
==========================================
  Files          45       46       +1     
  Lines        4726     4756      +30     
==========================================
+ Hits         3278     3321      +43     
+ Misses       1448     1435      -13     

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