feat(docs): add tabs and group tabs to improve documentation examples

[dzhalaevd]

What was wrong?

Users of pytest-asyncio can only pick auto or strict mode per project, but the docs show examples for both. Is kinda confusing, so we need add tabs

Closes: #641
Related: #641

How it was fixed?

• Add sphinx-tabs deps
• Update some doc files

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.13%. Comparing base (6a53907) to head (0a48269).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1395   +/-   ##
=======================================
  Coverage   95.13%   95.13%           
=======================================
  Files           2        2           
  Lines         473      473           
  Branches       57       57           
=======================================
  Hits          450      450           
  Misses         17       17           
  Partials        6        6           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[seifertm]

Thank you @dzhalaevd ! It will require reviewing the pytest-asyncio documentation to make use of this, but the sphinx-tab integration itself is valuable already.

Can you move the news fragment to the correct category as mentioned in the comment?

[seifertm]

Rather than mentioning this in the added category (as in "added features"), we should add this to the downstream category to notify downstream packagers of the added dependency.

[seifertm]

Suggested change

	Added ``sphinx-tabs`` to organize documentation examples into tabs.
	Added dependency on ``sphinx-tabs >= 3.5`` to organize documentation examples into tabs.