Default auto (#42805)
* default to `"auto"` dtype
* the actual change?
* up?
* style
* up?
* only sam models were broken with this
* fix sams
* update
* fix sam2 now
* up
* this?
* proper fix
* lol
* fix
* fixes
* nit
* fix
* fix copies
* fixes
* fix bigbird
* revert one bit
