Update PyPI PennyLane description

[josh146]

[github-actions[bot]]

Hello. You may have forgotten to update the changelog! Please edit doc/releases/changelog-dev.md with:

• A one-to-two sentence description of the change. You may include a small working example for new features.
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[josh146]

cc @lillian542 just to keep this on your radar --- this is a PR we would like to get into the 0.35 release!

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

:exclamation: No coverage uploaded for pull request base (v0.35.0-rc0@8dbe938). Click here to learn what that means.

Additional details and impacted files

@@              Coverage Diff               @@
##             v0.35.0-rc0    #5255   +/-   ##
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  Coverage               ?   99.67%           
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  Files                  ?      399           
  Lines                  ?    36585           
  Branches               ?        0           
==============================================
  Hits                   ?    36467           
  Misses                 ?      118           
  Partials               ?        0           

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