Rename BERT constraint to SBERT

[k-ivey]

What does this PR do?

Summary

This PR adds renames the BERT constraint, which is a sentence-level constraint using BERT, to SBERT to better reflect its functionality.

Additions

• Rename BERT constraint to SBERT.

Changes

• N/A

Deletions

• N/A

Checklist

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• [ X ] Make sure existing tests pass.
• [ ] Add relevant tests. No quality testing = no merge.
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[jxmorris12]

thanks this is a good change