Adds workflows model and workflow actions for Alerting Plugin

[eirsep]

PRs merged into feature branch feature/composite-monitors:
Added Alerting workflow model (#380)
Renamed chained monitor findings (#390)
Imports fixed (#394)
Added validation on IndexWorkflowRequest class (#405)
Extended deleted workflow response with list of monitor ids failed to delete (#416)

[codecov]

Codecov Report

Merging #439 (a1760ed) into main (85c9b35) will increase coverage by 0.80%.
The diff coverage is 78.90%.

@@             Coverage Diff              @@
##               main     #439      +/-   ##
============================================
+ Coverage     72.87%   73.67%   +0.80%     
- Complexity      712      804      +92     
============================================
  Files           113      125      +12     
  Lines          4711     5219     +508     
  Branches        606      662      +56     
============================================
+ Hits           3433     3845     +412     
- Misses         1024     1087      +63     
- Partials        254      287      +33     

Impacted Files	Coverage Δ
...org/opensearch/commons/alerting/util/IndexUtils.kt	53.33% <ø> (ø)
...search/commons/alerting/AlertingPluginInterface.kt	56.71% <57.14%> (+17.58%)	⬆️
...opensearch/commons/alerting/model/WorkflowInput.kt	57.14% <57.14%> (ø)
...rch/commons/alerting/action/GetWorkflowResponse.kt	57.50% <57.50%> (ø)
...h/commons/alerting/action/IndexWorkflowResponse.kt	70.00% <70.00%> (ø)
...n/org/opensearch/commons/alerting/model/Finding.kt	49.03% <70.83%> (+4.99%)	⬆️
.../commons/alerting/action/DeleteWorkflowResponse.kt	77.27% <77.27%> (ø)
...pensearch/commons/alerting/model/CompositeInput.kt	78.57% <78.57%> (ø)
...h/commons/alerting/model/ChainedMonitorFindings.kt	80.00% <80.00%> (ø)
.../org/opensearch/commons/alerting/model/Workflow.kt	80.74% <80.74%> (ø)
... and 6 more

... and 2 files with indirect coverage changes

[getsaurabh02]

I see three different names being used here in the PR - Workflows, ChainedMonitor and Composite. Wondering if we need to arrive at the consistency in naming, especially when UX and Rest APIs should be using Composite Monitors as the name.

[getsaurabh02]

Looks like some of these flows are not covered by the unit test. Consider looking into Codecov comments.

[eirsep]

I see three different names being used here in the PR - Workflows, ChainedMonitor and Composite. Wondering if we need to arrive at the consistency in naming, especially when UX and Rest APIs should be using Composite Monitors as the name.

Workflow refers to the the new type of scheduled job.
Composite is the input type - it accepts a sequence of monitors to be executed as input.
Chained Monitor refers to chained monitor findings i.e. findings of one monitor are used as the source data for the next monitor which is 'chained' to it.

[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-439-to-2.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 d088934defaa749c48022c41eaad5fd61fc84ec3
# Push it to GitHub
git push --set-upstream origin backport/backport-439-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-439-to-2.x.