* Respect sequence_len in config for `type: llama2_chat`
It was hardcoded to `4096` I am not sure why? This updates it to pull from the config.
cc: @winglian
* Update llama2_chat.py
* apply black formatting
* fix tokenizer
* update test data
* lint fixtures
* experimental llama 2 chat support
* few small fixes
* llama2_chat
* small fix to follow original implementation
* small fixes and added fixtures/tests
* fix -mixed up inference and finetuning conversations
* args - small fix
* small fix
* small adjustment and warning
* fix with pre-commit
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Co-authored-by: Jan Philipp Harries <jpdus@users.noreply.github.com>
