Changed model in t2c examples to gpt-3.5-turbo-0125

[willtai]

Description

gpt-3.5-turbo-instruct is not compatible any more with OpenAI's Chat Completions endpoint (see link). The Text2Cypher Retriever calls this endpoint. This PR updates the examples and documentation to change the model to gpt-3.5-turbo-0125.

Type of Change

• [ ] New feature
• [x] Bug fix
• [ ] Breaking change
• [ ] Documentation update
• [ ] Project configuration change

Complexity

Complexity: Low

How Has This Been Tested?

• [x] Unit tests
• [x] E2E tests
• [x] Manual tests

Checklist

The following requirements should have been met (depending on the changes in the branch):

• [x] Documentation has been updated
• [x] Unit tests have been updated
• [x] E2E tests have been updated
• [x] Examples have been updated
• [x] New files have copyright header
• [x] CLA (https://neo4j.com/developer/cla/) has been signed
• [ ] CHANGELOG.md updated if appropriate