[Extensions] Fixing BaseException imports and fixing Cluster Index Health request

[joshpalis]

Description

Fixes imports due to changes upstream : opensearch-project/OpenSearch#8035

Resolves AD stats API issue with null indices from Cluster health request by setting the cluster health request level to indices

Logs from testing stats API after creating a detector

dev-dsk-jpalis-2c-27c8aa11 % curl -XPOST "localhost:9200/_extensions/_ad-extension/detectors?pretty" -H "Content-Type:application/json" --data '{"name":"test-detector","description":"Test detector","time_field":"@timestamp","indices":["server_log"],"feature_attributes":[{"feature_name":"test","feature_enabled":true,"aggregation_query":{"test":{"avg":{"field":"jvmGcTime"}}}}],"detection_interval":{"period":{"interval":1,"unit":"Minutes"}},"window_delay":{"period":{"interval":1,"unit":"Minutes"}}}'
{
  "_id": "MS3P1YgBNCgmfjRHOqMe",
  "_version": 1,
  "_seq_no": 0,
  "anomaly_detector": {
    "name": "test-detector",
    "description": "Test detector",
    "time_field": "@timestamp",
    "indices": [
      "server_log"
    ],
    "filter_query": {
      "match_all": {
        "boost": 1
      }
    },
    "detection_interval": {
      "period": {
        "interval": 1,
        "unit": "Minutes"
      }
    },
    "window_delay": {
      "period": {
        "interval": 1,
        "unit": "Minutes"
      }
    },
    "shingle_size": 8,
    "schema_version": 0,
    "feature_attributes": [
      {
        "feature_id": "LAHP1YgBci4k6u0KNtDc",
        "feature_name": "test",
        "feature_enabled": true,
        "aggregation_query": {
          "test": {
            "avg": {
              "field": "jvmGcTime"
            }
          }
        }
      }
    ],
    "last_update_time": 1687214307861,
    "detector_type": "SINGLE_ENTITY"
  },
  "_primary_term": 1
}%                              

(23-06-19 22:38:27) <0> [~/repos/delete/anomaly-detection/dataGeneration]  
dev-dsk-jpalis-2c-27c8aa11 % curl -X GET "localhost:9200/_extensions/_ad-extension/stats/"
{
  "anomaly_detectors_index_status": "yellow",
  "anomaly_detection_state_status": "non-existent",
  "single_entity_detector_count": 1,
  "detector_count": 1,
  "multi_entity_detector_count": 0,
  "anomaly_detection_job_index_status": "non-existent",
  "models_checkpoint_index_status": "non-existent",
  "anomaly_results_index_status": "non-existent",
  "nodes": {
    "ad-extension": {
      "ad_execute_request_count": 0,
      "models": [],
      "ad_canceled_batch_task_count": 0,
      "ad_hc_execute_request_count": 0,
      "ad_hc_execute_failure_count": 0,
      "model_count": 0,
      "ad_execute_failure_count": 0,
      "ad_batch_task_failure_count": 0,
      "ad_total_batch_task_execution_count": 0,
      "ad_executing_batch_task_count": 0
    }
  }
}%        

Issues Resolved

opensearch-project/opensearch-sdk-java#674

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[joshpalis]

All tests have passed locally, haven't been able to reproduce the failing tests

[cwperks]

@joshpalis main needs to incorporate the changes from this PR as well: #928

[codecov]

Codecov Report

Merging #929 (8c6496c) into feature/extensions (54a6b1c) will decrease coverage by 0.02%.
The diff coverage is 90.90%.

@@                   Coverage Diff                    @@
##             feature/extensions     #929      +/-   ##
========================================================
- Coverage                 42.86%   42.84%   -0.02%     
  Complexity                 2420     2420              
========================================================
  Files                       301      301              
  Lines                     18168    18169       +1     
  Branches                   1873     1873              
========================================================
- Hits                       7787     7784       -3     
- Misses                     9806     9810       +4     
  Partials                    575      575              

Flag	Coverage Δ
plugin	42.84% <90.90%> (-0.02%)	⬇️

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

Impacted Files	Coverage Δ
...c/main/java/org/opensearch/ad/util/IndexUtils.java	1.31% <0.00%> (-0.02%)	⬇️
...common/exception/NotSerializedADExceptionName.java	76.74% <100.00%> (ø)

... and 2 files with indirect coverage changes