[ENH] Use Sphinx HTML assets policy to decide whether include assets

[humitos]

Sphinx v4.1.0 will include Sphinx.registry.html_assets_policy that defines the policy to whether include or not HTML assets in pages where the extension is not used.

This PR makes usage of this policy to decide if sphinx-tabs assets should be included or not in the page that's being rendered.

Reference: https://github.com/sphinx-doc/sphinx/issues/9115

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[codecov[bot]]

Codecov Report

Merging #127 (33e8075) into master (d921af3) will decrease coverage by 0.32%. The diff coverage is 80.00%.

@@            Coverage Diff             @@
##           master     #127      +/-   ##
==========================================
- Coverage   92.55%   92.23%   -0.33%     
==========================================
  Files           2        2              
  Lines         215      219       +4     
==========================================
+ Hits          199      202       +3     
- Misses         16       17       +1     

Flag	Coverage Δ
pytests	92.23% <80.00%> (-0.33%)	:arrow_down:

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
sphinx_tabs/tabs.py	92.16% <80.00%> (-0.33%)	:arrow_down:

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[foster999]

Thank @humitos, shall get the next version released including this change 😄

[humitos]

Thanks, @foster999 for continuing this work, and I'm sorry I wasn't able to make the latest required changes. I was on vacation 😃

[foster999]

No problem at all, hope you had a nice break! 😁