Fix `continue_final_message` in `apply_chat_template` to prevent substring matching issues (#40732)
* Fix continue_final_message parameter in apply_chat_template
* after run fixup
* Handle trim in the template
* after fixup
* Update src/transformers/utils/chat_template_utils.py
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Co-authored-by: Matt <Rocketknight1@users.noreply.github.com>