Add transformers extras

[probicheaux]

Description

Adds new extras install which install pytorch and other necessary dependencies for florence2, paligemma, and other transformers packages

Type of change

Please delete options that are not relevant.

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] This change requires a documentation update

How has this change been tested, please provide a testcase or example of how you tested the change?

Locally

Any specific deployment considerations

New extras wheel to be built

Docs

• [ ] Docs updated? What were the changes:

[probicheaux]

Addressing @PawelPeczek-Roboflow 's comments from https://github.com/roboflow/inference/pull/540

• lmm seems not to be good extras name Changed to inference[transformers]
• there is lack of tests confirming insatiability of new extras Added install tests
• there is no docs explaining how to use it - including the need for flashattn which is crutial Added a reference in the paligemma docs -- not quite sure about

  including the need for flashattn which is crucial

not sure how or why to document this package in particular

• all above are required for the submission to be accepted

[probicheaux]

Could you please add the transformers extras to https://github.com/roboflow/inference/blob/e601ad7898e35477ee872c8e92388d5b2a56b47b/docs/models.md#L91-L90

Added to extras table with warning about flash_attn

I forgot how much a pain that package is, we can't even install it in a fresh env becasue it needs packaging to install. If we want to make sure that stuff is getting installed correctly, we should probably start work on an install script for inference

[PawelPeczek-Roboflow]

@probicheaux this PR was reverted due to failing CI