chore(backport release-1.3): docs: add v1.3.0 release notes

[akuitybot]

Automated backport to release-1.3, triggered by a label in #3565.

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 52.64%. Comparing base (16dfa85) to head (b8ecca3).
Report is 1 commits behind head on release-1.3.

Additional details and impacted files

@@             Coverage Diff              @@
##           release-1.3    #3571   +/-   ##
============================================
  Coverage        52.64%   52.64%           
============================================
  Files              296      296           
  Lines            26875    26875           
============================================
  Hits             14149    14149           
  Misses           11952    11952           
  Partials           774      774           

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