GitLab

* 4d mask fixes

* Update custom 4D mask logic

* test moved to mixin

* extra tests 4d mask

* upd 4d mask and StaticCache handling

* added Mask4DTestHard to mistral tests

* post-rebase fixes

* test fixes for StaticCache

* make fix-copies

* upd 1 after #30476

* fix common tests

* rm elif attention_mask.dim() == 4:

* tests combined, fixed, mixtral supported

* bigbird style chg reverted

* rm if attention_mask.dim() == 2

* modeling_llama formatting chg

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Co-authored-by: Joao Gante <joao@huggingface.co>