Remove BertConfig inheritance from RobertaConfig
Author: Saad135
Pull request: yes

# What does this PR do?

Removes BertConfig dependencies from RobertaConfig

Related to https://github.com/huggingface/transformers/issues/19303

@sgugger can I please get some feedback on this. Thanks 😄

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Models:

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Comments:
_The documentation is not available anymore as the PR was closed or merged._

Thanks again for your contribution!