Post-release documentation updates

[chmwzc]

Changes:

• Updated the installation instructions and Quickstart pages to reflect that Qibochem has been released and can be installed from PyPI directly
• Changed landing page of the main documentation page from 'latest' to 'stable' to match the other Qibo-related repositories
• Updated README.md to match the other Qibo-related repositories as well

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (115904e) 100.00% compared to head (a8512fa) 100.00%.

Additional details and impacted files

@@            Coverage Diff            @@
##              main       #70   +/-   ##
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  Coverage   100.00%   100.00%           
=========================================
  Files           11        11           
  Lines          401       401           
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  Hits           401       401           

Flag	Coverage Δ
unittests	100.00% <ø> (ø)

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[damarkian]

Thanks for this.

Since we are omitting psi4 support for now, maybe we should remove it in the README.md?

[chmwzc]

Yup, it's been taken out from README.md👍