Update example in iBeacon.md

Point example to latest version.

Author: Amanda Butler

docs/api/bluetooth/iBeacon.md

@@ -12,6 +12,6 @@ The iBeacon class builds an advertising payload mimicking an iBeacon and assigns
 
 ### iBeacon example
 
-[![View code](https://www.mbed.com/embed/?url=https://os.mbed.com/teams/mbed-os-examples/code/mbed-os-example-ble-Beacon/)](https://os.mbed.com/teams/mbed-os-examples/code/mbed-os-example-ble-Beacon/file/5575d1bee775/source/main.cpp)
+[![View code](https://www.mbed.com/embed/?url=https://os.mbed.com/teams/mbed-os-examples/code/mbed-os-example-ble-Beacon/)](https://os.mbed.com/teams/mbed-os-examples/code/mbed-os-example-ble-Beacon/file/ec76013cdcab/source/main.cpp)
 
 <span class="notes">**Note:** You can find more information at the [Apple iBeacon page](https://developer.apple.com/ibeacon/).</span>