Delete link in BLE.md

Delete broken link, so engine can build.

Author: Amanda Butler

docs/reference/api/connectivity/bluetooth/BLE.md

@@ -6,8 +6,6 @@ Arm Mbed BLE, also called `BLE_API`, is the Bluetooth Low Energy software soluti
 
 ### BLE class reference
 
-[![View code](https://www.mbed.com/embed/?type=library)](https://os-doc-builder.test.mbed.com/docs/v5.7/mbed-os-api-doxy/class_b_l_e.html)
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 ### Usage
 
 1. Set up advertising and connection modes.