Fix #4046 Details below: (#4086)

Informed by the discussion in the bug and the code in 'that other branch'
the fix was clear.  Just set a flag if we start handling a write, and
use that flag to guard the long write complete call.

libraries/BLE/src/BLECharacteristic.h

@@ -107,6 +107,7 @@ private:
 	BLEService*                 m_pService;
 	BLEValue                    m_value;
 	esp_gatt_perm_t             m_permissions = ESP_GATT_PERM_READ | ESP_GATT_PERM_WRITE;
+	bool						m_writeEvt = false; // If we have started a long write, this tells the commit code that we were the target
 
 	void handleGATTServerEvent(
 			esp_gatts_cb_event_t      event,