Adds webhook format check for Chime

[Noir01]

Description

Adds webhook format check for Chime

Issues Resolved

fixes #788

Check List

• Commits are signed per the DCO using --signoff

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.
For more information on following Developer Certificate of Origin and signing off your commits, please check here.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 66.93%. Comparing base (87109a0) to head (0ebbd73).
Report is 21 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main     #816      +/-   ##
============================================
+ Coverage     66.89%   66.93%   +0.03%     
- Complexity      265      267       +2     
============================================
  Files            39       39              
  Lines          1740     1742       +2     
  Branches        165      165              
============================================
+ Hits           1164     1166       +2     
  Misses          453      453              
  Partials        123      123              

Flag	Coverage Δ
opensearch-notifications	66.93% <100.00%> (+0.03%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[Noir01]

Should I add new tests for this like I did in #814 ?

[Hailong-am]

Should I add new tests for this like I did in #787 ?

Yes, please.

[Noir01]

Should I add new tests for this like I did in #787 ?

Yes, please.

Done.

[zhichao-aws]

lgtm

[eirsep]

@Noir01 will this be backported to 2.x versions?
plz let us know so that we can do corresponding backports in alerting plugin too

[Hailong-am]

@Noir01 will this be backported to 2.x versions? plz let us know so that we can do corresponding backports in alerting plugin too

@eirsep Consider the backward capability we are not going to backport to 2.x for coming 2.12 realsee.

[opensearch-trigger-bot]

The backport to 2.10 failed:

The process '/usr/bin/git' failed with exit code 128

To backport manually, run these commands in your terminal:

# Navigate to the root of your repository
cd $(git rev-parse --show-toplevel)
# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add ../.worktrees/notifications/backport-2.10 2.10
# Navigate to the new working tree
pushd ../.worktrees/notifications/backport-2.10
# Create a new branch
git switch --create backport/backport-816-to-2.10
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 1163d542a6028faeb7941349ea9232f1c490a45d
# Push it to GitHub
git push --set-upstream origin backport/backport-816-to-2.10
# Go back to the original working tree
popd
# Delete the working tree
git worktree remove ../.worktrees/notifications/backport-2.10

Then, create a pull request where the base branch is 2.10 and the compare/head branch is backport/backport-816-to-2.10.