[Doc] Improve ra-realtime doc to unlock record

[erwanMarmelab]

Problem

EE doc was updated

Solution

Update OSS doc

Additional Checks

• The PR targets master for a bugfix or a documentation fix, or next for a feature
• [ ] The PR includes unit tests (if not possible, describe why)
• [ ] The PR includes one or several stories (if not possible, describe why)
• The documentation is up to date

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[djhi]

Actually the entreprise doc should have been updated to remove this as we now block the navigation until the record is unlocked. We don't need to update the doc at all