Add minimal list of requirements for SAST analyzers

What does this MR do?

SAST, as a feature category, has a rather large list of features. However, we had not previously documented the features which belong specifically to SAST analyzers. This MR attempts to articulate this information and declare a minimum feature set a new analyzer must have for it to be declared generally available.

Screenshots (strongly suggested)

Does this MR meet the acceptance criteria?

Conformity

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  • I have not included a changelog entry because _____.
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

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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• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
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