Remove attribute sanitization from DOMPurify configuration

What does this MR do?

Due to a bug in DOMPurify, we had to implement potentially dangerous data-* attribute sanitization using hooks. These checks can be removed now as they are no longer needed.

This will allow v-safe-html to configure if it should allow these attributes for inputs that are safe.

This reverts changes (except specs) introduced in !65301 (merged).

Screenshots or Screencasts (strongly suggested)

NA

Does this MR meet the acceptance criteria?

Conformity

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Security

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Related to #335684 (closed)