Opensearch Upgrade from 1.2.x to 2.4 Documentation

Versions (relevant - OpenSearch/Dashboard/Server OS/Browser): 1.2.4

Describe the issue: I am planning for a upgrade from version 1.2.x to version 2.4.0 . I could not find the relevant documentation for this. Please help to get the right document.

Configuration: NA

Relevant Logs or Screenshots: NA

Unfortunately, there is no detailed information. You can do an upgrade with a full-cluster restart, however, doing a rolling upgrade requires you to first upgrade to v1.3 and then do a foolow up rolling upgrade (due to