Update admin docs to clarify helm charts installs

What does this MR do?

This MR attempts to update the Admin documentation for enabling the Packages feature for Helm Chart installs. While I was there, I also cleaned up the supported formats table to match the user docs.

Closes: #248316 (closed)

Screenshots (strongly suggested)

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