Add changelog for 13.1.0

[alperkocatas]

Add changelog entries for 13.1.0.

The list of changes was constructed using the following method:

• include set of commits that come up in comparison of release-13.1 and release-13.0 branch
• exclude changes in 13.0.0, 13.0.1, 13.0.2 and 13.0.3
• exclude changes related to database sharding
• exclude changes that were cherry picked from main and released before 13.1
• review remaining commits and exclude non user-facing commits.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.19%. Comparing base (e428471) to head (ec617b8).
Report is 1 commits behind head on release-13.1.

Additional details and impacted files

@@               Coverage Diff                @@
##           release-13.1    #8006      +/-   ##
================================================
- Coverage         89.20%   89.19%   -0.02%     
================================================
  Files               284      284              
  Lines             61515    61516       +1     
  Branches           7696     7697       +1     
================================================
- Hits              54875    54869       -6     
- Misses             4437     4441       +4     
- Partials           2203     2206       +3     

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[onurctirtir]

Left some suggestions on some changelog entries, please consider addressing them.

After that, I suggest working with @naisila on grouping of the similar features and possibly re-ordering some of them etc.

[naisila]

After addressing first round of reviews, we can work on combining and reordering. Thank you Alper and Onur.