fix from_pretrained in offline mode when model is preloaded in cache

[oOraph]

What does this PR do?

Fixes # (issue) fix model load in offline mode

Who can review?

@ArthurZucker @Wauplin

Reproduce:

1. download a private model from hub
2. script:

import os

os.environ['TRANSFORMERS_OFFLINE'] = "true"

from transformers.models.auto.modeling_auto import AutoModelForImageClassification

model_id = "Narsil/private"
revision = "main"
kwargs = {'use_auth_token': None}


model = AutoModelForImageClassification.from_pretrained(model_id, revision=revision, **kwargs)

[HuggingFaceDocBuilderDev]

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[oOraph]

Thanks! Can you add this example by using HF hub to downlaod snapshot of a .bin file in a temp repo? and test both the flag to go offline and the local_files_only in from pretrained? 🤗

Done @ArthurZucker , added some unit test -> fails before fix, succeeds after test is ugly but I could not find any cleaner way to do it...