[Docs] Fix bullets and grammars in tool_calling.md

[windsonsea]

Only fixed some grammar issues and bullets list, without any meaning changed.

docs/features/tool_calling.md

[gemini-code-assist]

Code Review

This pull request provides several small but valuable fixes to the tool_calling.md documentation. The changes include correcting grammar, improving wording for clarity, fixing punctuation, and ensuring consistent formatting for lists and headings. These improvements enhance the readability and correctness of the documentation. The changes are well-contained and look good to merge.

[DarkLight1337]

Thanks for polishing the docs!

[github-actions]

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