Schema validation error property L2bridge can't be empty object

This article shows how to resolve "Schema validation error. property 'l2bridge' can't be empty object".

*When WLAN is bridged to LAN.

*When the firmware version is on 7.0.0-R906.

If the firmware is on 7.0.0-R906 upgrade the firmware to the latest version. This issue was fixed in the latest version.
1.Upgrade the firmware to the latest version by following this KB article 

How can I upgrade SonicOS Firmware?
2.Once upgrading the firmware to the latest version, 
3.Navigate to Network|Interfaces|WLAN Interface, edit WLAN.

4.Now we can able to enable HTTPS and ping on the interface.