Geo: Document Resync and Reverify actions in Troubleshooting docs

What does this MR do and why?

This MR improves the Geo troubleshooting section, specifically the Manually retry replication or verification section to include the resync and reverify actions through UI released on %16.2.

It also reorganizes the given Rails commands to encapsulate the ones that affect individual or multiple registries in their corresponding sections.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #417179