[ML] Increase Test Coverage 8.5.0

[peteharverson]

Follow up to #133871

Meta issue to summarize improvements to test coverage for 8.5.0.

Jest unit tests

• aiops:query_utils/buildBaseFilterCriteria (WR)
  [ML] Explain Log Rate Spikes: Adds jest tests for query_utils/buildBaseFilterCriteria. #141213
• Transform install in Fleet (QA)
  [ML] Fix bug with fields.yml not defined, add jest tests for new transform installation mechanism in Fleet #142159
• Transforms - preserves field when edited aggs not supported in the wizard
  [ML] Transforms: Preserves the field for unsupported aggs #142106

API integration tests

• POST /api/ml/jobs/jobs [ML] api/ml/jobs/jobs api tests #142234
• POST /api/ml/jobs/jobs_summary Already covered here
• GET /api/ml/modules/jobs_exist/:moduleId [ML] Api tests for ml/modules/jobs_exist/{moduleId} #142378
• POST /api/ml/saved_objects/remove_item_from_current_space [ML] Api tests for ml/saved_objects/remove_item_from_current_space #142319
• POST /api/ml/results/anomaly_search [ML] Api tests for ml/results/anomaly_search #142454
• GET /api/ml/notifications (DA) [ML] Update the Notification indicator tooltip, add functional tests  #141775
• GET /api/ml/notifications/count (DA) [ML] Update the Notification indicator tooltip, add functional tests  #141775

Functional tests

• Creating ML jobs directly from Lens (JG)
  [ML] Quickly create ML jobs from lens visualizations #136421
• DFA wizard with saved search filters (PH)
  [ML] Adds functional tests for data frame analytics jobs with filters #139935
• Fix flaky transform creation test (WR)
  [ML] Transforms: Fix flaky wizard functional tests. #141209
• Notifications page (DA)
  [ML] Update the Notification indicator tooltip, add functional tests  #141775
• Explain Log Rate Spikes: Group results (WR)
  [ML] Explain Log Rate Spikes: Fix grouping edge cases. #140891

Accessibility tests

part of #88496

• Multi-metric job wizard (PH)
  [ML] Adds extra a11y tests for anomaly detection and DFA jobs #142589
• Forecast modal (Single Metric Viewer) (PH)
  [ML] Adds extra a11y tests for anomaly detection and DFA jobs #142589
• DFA create regression job (PH)
  [ML] Adds extra a11y tests for anomaly detection and DFA jobs #142589
• DFA create classification job (PH)
  [ML] Adds extra a11y tests for anomaly detection and DFA jobs #142589

[elasticmachine]

Pinging @elastic/ml-ui (:ml)

[peteharverson]

Closing issue as all the tests planned for 8.5.0 have now been added.