fix: DIA-1988: Replace Custom endpoint with OpenAI client

[robot-ci-heartex]

This PR was automatically generated via Follow Merge. Workflow Run
Please ensure that all linked upstream Pull Requests are merged before proceeding with this one.

• Adjust schema for using PredictedOutputs label-studio-sdk#424

[netlify]

✅ Deploy Preview for label-studio-docs-new-theme canceled.

Name	Link
🔨 Latest commit	9df1a0a
🔍 Latest deploy log	https://app.netlify.com/sites/label-studio-docs-new-theme/deploys/67c1eaf31936980008e3f5e9

[netlify]

✅ Deploy Preview for heartex-docs canceled.

Name	Link
🔨 Latest commit	9df1a0a
🔍 Latest deploy log	https://app.netlify.com/sites/heartex-docs/deploys/67c1eaf375ed960008e23527

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 77.20%. Comparing base (58648d1) to head (9df1a0a).
Report is 1 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #7150   +/-   ##
========================================
  Coverage    77.20%   77.20%           
========================================
  Files          187      187           
  Lines        14480    14480           
========================================
  Hits         11179    11179           
  Misses        3301     3301           

Flag	Coverage Δ
pytests	77.20% <ø> (ø)

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

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.