fix: Fix warning by AmazonBedrockChatGenerator

[alperkaya]

Related Issues

• fixes #1113

Proposed Changes:

How did you test it?

CI

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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:.