docs: Update changelog for 3.1 release

[cloudxxx8]

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• [x] I am not introducing a breaking change (if you are, flag in conventional commit message with BREAKING CHANGE: describing the break)
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[codecov-commenter]

Codecov Report

Merging #311 (9b45417) into main (a408643) will not change coverage. The diff coverage is n/a.

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@@          Coverage Diff          @@
##            main    #311   +/-   ##
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  Coverage   4.75%   4.75%           
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  Files          8       8           
  Lines       1305    1305           
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  Hits          62      62           
  Misses      1243    1243