Add `chat_template` (`jinja2`) as an extra dependency (#40128)
* add jinja2 as a dependency
* Make jinja2 a core dependency in install_requires
- Add jinja2 to install_requires list in setup.py for automatic installation
- Add jinja2 to runtime version checks in dependency_versions_check.py
- Resolves issue where pip install transformers doesn't install jinja2
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Co-Authored-By: Claude <noreply@anthropic.com>
* Make jinja2 a core dependency in install_requires
* Make jinja2 an extra dependency instead of adding a core dep
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Co-authored-by: Claude <noreply@anthropic.com>