Throw an error when yaml mode contains unparsable attributes

What does this MR do?

Issue: #271169 (closed)

This MR fixes an error that occurs on the Security & Compliance -> Threat Monitoring -> Policies page. When users create or edit a policy and enter L7 policies in yaml mode, the L7 portion of the policy is currently removed from the yaml if the user then switches into rule mode. The desired behavior is to throw an error instead of stripping the policy. This update fixes that bug by checking whether or not the user-entered yaml contains any attributes that we do not recognize.

Screenshots (strongly suggested)

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
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Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
• Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Security

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