docs: Proofread primary key feature docs

[DeflateAwning]

Motivation

• A few typos and formatting issues

Changes

• Fixed the few typos and formatting issues, hopefully

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (cf2b98a) to head (a2d974c).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main      #161   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           51        51           
  Lines         2896      2896           
=========================================
  Hits          2896      2896           

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[borchero]

Thank you!