Updates 2.12.0 release notes

[DarshitChanpura]

Adds #1298 and #1318 to the release notes.

Check List

- [ ] New functionality includes testing.
- [ ] All tests pass
- [ ] New functionality has been documented.
- [ ] New functionality has javadoc added

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (d703887) 76.36% compared to head (c30a969) 76.62%.

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #1329      +/-   ##
============================================
+ Coverage     76.36%   76.62%   +0.25%     
+ Complexity     1050     1049       -1     
============================================
  Files           141      141              
  Lines          4782     4782              
  Branches        526      526              
============================================
+ Hits           3652     3664      +12     
+ Misses          776      768       -8     
+ Partials        354      350       -4     

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[opensearch-trigger-bot]

The backport to 2.x failed:

The process '/usr/bin/git' failed with exit code 1

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-2.x 2.x
# Navigate to the new working tree
cd .worktrees/backport-2.x
# Create a new branch
git switch --create backport/backport-1329-to-2.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 3f4f2163d61ff660d608c39412802dea383a8426
# Push it to GitHub
git push --set-upstream origin backport/backport-1329-to-2.x
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-2.x

Then, create a pull request where the base branch is 2.x and the compare/head branch is backport/backport-1329-to-2.x.