Docs: Remove deprecated SAST analyzers

What does this MR do?

Summary: Update documentation to reflect the %15.0 SAST analyzer consolidations and CI/CD template changes.

Details: I reviewed Documenting product versions and tried to make reasonable choices in each context. I'm definitely open to suggestions or feedback on this—just wanted to take a first pass at least!

I specifically did not try to remove all examples that refer to deprecated analyzers. This is for two reasons:

1. The examples may be useful to customers on previous versions
2. I feel that replacing the examples with new examples would delay this MR (and it is beyond the scope of an MVC)

Related issues/content

• Deprecation announcement: SAST analyzer consolidation and CI/CD template changes
• Deprecation issue: SAST Deprecation: Analyzer consolidation and CI... (#352554 - closed)
• MRs to change the template: SAST Deprecations for 15.2 release: eslint, ban... (!86013 - closed). (There are a variety of other MRs with dependent changes.)

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Reviewer's checklist

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