Cherry-picking commits for 1.3 release from main to 1.x

[AWSHurneyt]

Issue #, if available:
#314

Description of changes:
Cherry-picking commits df65ffc through 9487c00 from opensearch-project/alerting/main to opensearch-project/alerting/1.x.

CheckList:
[x] 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-commenter]

Codecov Report

Merging #345 (3b5799e) into 1.x (cfdbe73) will decrease coverage by 0.20%.
The diff coverage is 70.91%.

@@             Coverage Diff              @@
##                1.x     #345      +/-   ##
============================================
- Coverage     78.46%   78.26%   -0.21%     
- Complexity      214      265      +51     
============================================
  Files           173      176       +3     
  Lines          6975     7223     +248     
  Branches        916      960      +44     
============================================
+ Hits           5473     5653     +180     
- Misses         1011     1069      +58     
- Partials        491      501      +10     

Impacted Files	Coverage Δ
...erting/settings/SupportedClusterMetricsSettings.kt	19.51% <19.51%> (ø)
.../util/SupportedClusterMetricsSettingsExtensions.kt	35.41% <35.41%> (ø)
...ain/kotlin/org/opensearch/alerting/InputService.kt	88.57% <75.00%> (+0.69%)	⬆️
...in/kotlin/org/opensearch/alerting/model/Monitor.kt	88.67% <85.71%> (-0.29%)	⬇️
...nsearch/alerting/core/model/ClusterMetricsInput.kt	95.30% <95.30%> (ø)
...n/kotlin/org/opensearch/alerting/AlertingPlugin.kt	94.73% <100.00%> (+0.03%)	⬆️
...lerting/transport/TransportExecuteMonitorAction.kt	71.11% <0.00%> (-2.23%)	⬇️
.../alerting/transport/TransportIndexMonitorAction.kt	59.52% <0.00%> (+0.47%)	⬆️
.../kotlin/org/opensearch/alerting/core/JobSweeper.kt	72.00% <0.00%> (+0.50%)	⬆️
... and 2 more

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