fix: updating LLMMetaDataExtractor example code + notebook

[davidsbatista]

Proposed Changes:

• Adding an example notebook on how to use the LLMMetaDataExtractor
• Unless the word json is specified in the prompt OpenAI complains about the output format being in JSON, even with the "response_format": {"type": "json_object"} set

How did you test it?

• manual verification

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

[review-notebook-app]

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[julian-risch]

LGTM! 👍
I also ran the notebook on Google colab and it worked: https://colab.research.google.com/github/deepset-ai/haystack-experimental/blob/update-llmmetadataextract-prompt/examples/metadata_extraction_with_llm_metadata_extractor.ipynb

[coveralls]

Pull Request Test Coverage Report for Build 12866505599

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 78.679%

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Totals
Change from base Build 12865814691:	0.0%
Covered Lines:	1358
Relevant Lines:	1726

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💛 - Coveralls