[Backport 2.x] Adding custom plugin to publish zip to maven

[opensearch-trigger-bot]

Backport 6e373a7 from #594

[codecov-commenter]

Codecov Report

Merging #595 (6e373a7) into 2.x (868db97) will decrease coverage by 0.26%.
The diff coverage is 79.83%.

❗ Current head 6e373a7 differs from pull request most recent head 87189bb. Consider uploading reports for the commit 87189bb to get more accurate results

@@             Coverage Diff              @@
##                2.x     #595      +/-   ##
============================================
- Coverage     79.28%   79.02%   -0.27%     
+ Complexity     4226     4209      -17     
============================================
  Files           296      296              
  Lines         17686    17685       -1     
  Branches       1880     1880              
============================================
- Hits          14023    13975      -48     
- Misses         2772     2811      +39     
- Partials        891      899       +8     

Flag	Coverage Δ
plugin	79.02% <79.83%> (-0.27%)	⬇️

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

Impacted Files	Coverage Δ
.../main/java/org/opensearch/ad/ml/CheckpointDao.java	69.55% <ø> (ø)
...n/java/org/opensearch/ad/ml/EntityColdStarter.java	81.92% <62.96%> (ø)
.../transport/SearchAnomalyResultTransportAction.java	84.11% <83.13%> (ø)
.../java/org/opensearch/ad/AnomalyDetectorPlugin.java	96.53% <100.00%> (ø)
.../opensearch/ad/ratelimit/CheckpointReadWorker.java	87.68% <100.00%> (ø)
...va/org/opensearch/ad/settings/AbstractSetting.java	90.90% <100.00%> (ø)
...ava/org/opensearch/ad/settings/EnabledSetting.java	100.00% <100.00%> (ø)
.../java/org/opensearch/ad/AnomalyDetectorRunner.java	37.64% <0.00%> (-5.89%)	⬇️
...java/org/opensearch/ad/task/ADBatchTaskRunner.java	81.76% <0.00%> (-4.56%)	⬇️
...ava/org/opensearch/ad/task/ADHCBatchTaskCache.java	90.12% <0.00%> (-2.47%)	⬇️
... and 10 more