[8.16] Updates manual run docs (backport #6800)

[mergify]

Description

This PR continues the work of #6799 and makes the following changes to the 8.16 and 8.17 manual rule run docs:

• Docs longstanding known issues as feature limitations.
• Adds minor organizational improvements to align with the 8.18 docs.
• Fixes the screenshot of the Manual runs table, which was in beta for 8.16 and 8.17.

Preview

• Run rules manually
• Manual runs table

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  This is an automatic backport of pull request Updates manual run docs #6800 done by Mergify.

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