adding alerting comments security actions to roles.yml

[toepkerd]

Description

Adding new alerting comments security permissions to existing alerting plugin roles for new Alerting Comments feature: opensearch-project/alerting#1561

• Category: Addition as part of new feature
• Why these changes are required?: to ensure proper and intended permissioning of comments in the alerting plugin
• What is the old behavior before changes and new behavior after changes?: before the changes, there was no way to specify what users and what roles had access to what comments. This change allows for that to happen.

Issues Resolved

[List any issues this PR will resolve]

Is this a backport? If so, please add backport PR # and/or commits #, and remove backport-failed label from the original PR.
Not a backport PR, but would like this PR backported to 2.15

Do these changes introduce new permission(s) to be displayed in the static dropdown on the front-end? If so, please open a draft PR in the security dashboards plugin and link the draft PR here
New permissions are added but are best included under existing alerting plugin roles

Testing

[Please provide details of testing done: unit testing, integration testing and manual testing]

Check List

• New functionality includes testing
• New functionality has been documented
• New Roles/Permissions have a corresponding security dashboards plugin PR
• API changes companion pull request created
• 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 65.25%. Comparing base (6735b5c) to head (a59345f).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4699      +/-   ##
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+ Coverage   65.20%   65.25%   +0.04%     
==========================================
  Files         318      318              
  Lines       22327    22327              
  Branches     3591     3591              
==========================================
+ Hits        14558    14569      +11     
+ Misses       5971     5960      -11     
  Partials     1798     1798              

see 3 files with indirect coverage changes