Delete deprecated stuff (#38838)
* delete deprecated stuff
* fix copies
* remove unused tests
* fix modernbert and fuyu
* Update src/transformers/cache_utils.py
Co-authored-by: Joao Gante <joaofranciscocardosogante@gmail.com>
* bye bye `seen_tokens`
* address comments
* update typings
* ecnoder decoder models follow same pattern as whisper
* fix copies
* why is it set to False?
* fix switch transformers
* fix encoder decoder models shared weight
* fix copies and RAG
* remove `next_cache`
* fix gptj/git
* fix copies
* fix copies
* style...
* another forgotten docsrting
---------
Co-authored-by: Joao Gante <joaofranciscocardosogante@gmail.com>
