Move secure eslint analyzer to core

What does this MR do?

• Remove required check for sast feature in CI template
• Document when eslint analyzer was moved to core
• Document that Docker-in-Docker wouldn`t be supported in core analyzers

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• 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

Related Issues

• #34707 (closed)