DOC-2366: Add revision history diff API

[tiny-ben-tran]

Site: link - #diff

Description of changes:

• Documented diff() API of the Revision history doc
• Removed orphan accordion_apis.adoc and cleaned up

Pre-checks:

• [x] Branch prefixed with feature/<version>/, hotfix/<version>/, staging/<version>/, or release/<version>/
• [x] modules/ROOT/nav.adoc has been updated (if applicable)
• [x] Files has been included where required (if applicable)
• [x] Files removed have been deleted, not just excluded from the build (if applicable)
• [x] Files added for New product features, and included a release note entry.

Review:

• [x] Documentation Team Lead has reviewed