Improve PyCharm and Colab notebook documentation

[MarcSkovMadsen]

Closes #6567. Also adds some extra info to the Colab guide.

[MarcSkovMadsen]

@cdeil . I can't have PyCharm Professional installed for security reasons. Could you review and improve this PR? Thx.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 40.01%. Comparing base (2a35d9c) to head (65a58a7).
Report is 10 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #6599       +/-   ##
===========================================
- Coverage   82.98%   40.01%   -42.98%     
===========================================
  Files         313      313               
  Lines       46073    46105       +32     
===========================================
- Hits        38235    18447    -19788     
- Misses       7838    27658    +19820     

Flag	Coverage Δ
ui-tests	40.01% <ø> (-0.04%)	⬇️
unitexamples-tests	?

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[cdeil]

Actually today I can't get Panel to work in either VSCode or PyCharm notebooks if I install the latest Panel 1.4 in a fresh conda env (see https://gist.github.com/cdeil/50757a6d425c0764c266e23eee5e0329 )

I get different errors that I presume are bugs or incompatibilities in the various involved packages?

[philippjfr]

I get different errors that I presume are bugs or incompatibilities in the various involved packages?

Does a regular ipywidget work?

[MarcSkovMadsen]

For me Panel 1.4.0 works in VS Code. Not on first attempt but if I try again. Described in #6640.

[philippjfr]

Merging as-is for now but would be nice to figure out the remaining issues in VSCode and figure out the new PyCharm issue.