Change WorkflowData from interface to class

[dbwiddis]

Description

Simplifies WorkflowData by making it a POJO.

Note: Impacts PRs #47, #38, #44, and #52. Happy to rebase this after those are merged if they are ready to go, or we can merge this and rebase those.

Issues Resolved

Fixes #53

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[codecov]

Codecov Report

Merging #54 (a2b0bd4) into main (a97b7d0) will decrease coverage by 6.82%.
The diff coverage is 80.00%.

❗ Current head a2b0bd4 differs from pull request most recent head ee99427. Consider uploading reports for the commit ee99427 to get more accurate results

@@             Coverage Diff              @@
##               main      #54      +/-   ##
============================================
- Coverage     75.14%   68.33%   -6.82%     
- Complexity       47       48       +1     
============================================
  Files             7        7              
  Lines           173      180       +7     
  Branches         18       18              
============================================
- Hits            130      123       -7     
- Misses           32       48      +16     
+ Partials         11        9       -2     

Files	Coverage Δ
...ramework/workflow/CreateIndex/CreateIndexStep.java	84.84% <100.00%> (-0.45%)	⬇️
...pensearch/flowframework/workflow/WorkflowData.java	100.00% <100.00%> (ø)
...nsearch/flowframework/template/TemplateParser.java	91.66% <0.00%> (ø)

... and 1 file with indirect coverage changes

[dbwiddis]

Note the changes required in the other PRs are minimal/trivial, so merging this first if there's still any iteration on your PRs will be a benefit.

- future.complete(new WorkflowData() {
-     @Override
-     public Map<String, Object> getContent() {
-         return Map.of("index-name", createIndexResponse.index());
-     }
- });
+ future.complete(new WorkflowData(Map.of("index-name", createIndexResponse.index())));

[owaiskazi19]

Note the changes required in the other PRs are minimal/trivial, so merging this first if there's still any iteration on your PRs will be a benefit.

- future.complete(new WorkflowData() {
-     @Override
-     public Map<String, Object> getContent() {
-         return Map.of("index-name", createIndexResponse.index());
-     }
- });
+ future.complete(new WorkflowData(Map.of("index-name", createIndexResponse.index())));

Ah! Missed this. Let me take care of this in my followup PR.

[owaiskazi19]

Thanks for this change!