doc: warning added for deprectaion of `gpt-3.5` as default model for OpenAI generators

[alperkaya]

Related Issues

• fixes #8222

Proposed Changes:

• warning message added to the generators init()

How did you test it?

• CI tests

Checklist

• I have read the contributors guidelines and the code of conduct
• I have updated the related issue with new insights and changes
• I added unit tests and updated the docstrings
• I've used one of the conventional commit types for my PR title: fix:, feat:, build:, chore:, ci:, docs:, style:, refactor:, perf:, test:.
• I documented my code
• I ran pre-commit hooks and fixed any issue

[CLAassistant]

All committers have signed the CLA.

[alperkaya]

@davidsbatista

[davidsbatista]

no need to add the warning to the tests just in the initialisation of the following components:

• OpenAIChatGenerator
• OpenAIGenerator

[davidsbatista]

@alperkaya please sign the Contributor License Agreement otherwise this can't be merged.

Just a few notes:

• Be sure to fill in the PR comments giving a bit more details as the template suggests.
• Give a more complete title to the PR and be sure to add the prefix.
• When in doubt ask/comment in the PR comments.

And thank you once again for the initiative, appreciated!

[coveralls]

Pull Request Test Coverage Report for Build 10603913624

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 16 unchanged lines in 2 files lost coverage.
• Overall coverage increased (+0.005%) to 90.197%

---

Files with Coverage Reduction	New Missed Lines	%
components/generators/openai.py	3	96.51%
components/generators/chat/openai.py	13	79.65%
<!--	Total:	16

Totals
Change from base Build 10598482118:	0.005%
Covered Lines:	7002
Relevant Lines:	7763

---

💛 - Coveralls

[alperkaya]

@alperkaya please sign the Contributor License Agreement otherwise this can't be merged.

Just a few notes:

* Be sure to fill in the PR comments giving a bit more details as the template suggests.

* Give a more complete title to the PR and be sure to add the prefix.

* When in doubt ask/comment in the PR comments.

And thank you once again for the initiative, appreciated!

Hi @davidsbatista,

Thank you for clear instructions and descriptions. I just sign the license. I hope it is ready for merge now.