Pin elasticsearch to version 7.17.4 for testing

[julian-risch]

Related Issues

• As part of the support of elasticsearch 8, this PR is related to https://github.com/deepset-ai/haystack/issues/2810

Proposed Changes:

How did you test it?

Notes for the reviewer

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 tests that demonstrate the correct behavior of the change
• [ ] I've used the conventional commit convention for my PR title
• [ ] I documented my code
• [ ] I ran pre-commit hooks and fixed any issue