Change docs type in insert_many to list of dicts

[MezentsevIlya]

Hello! In the insert_many method signature docs argument type is dict, but actually it must be list of dicts: list[dict]

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[boring-cyborg]

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[jedcunningham]

Static check failure is unrelated (see #37251).

[boring-cyborg]

Awesome work, congrats on your first merged pull request! You are invited to check our Issue Tracker for additional contributions.

[jedcunningham]

Thanks @MezentsevIlya! Congrats on your first commit 🎉