Fixed leftover include in stm32wb app

Author: danielinux

test-app/app_stm32wb.c

@@ -27,7 +27,6 @@
 #include "led.h"
 #include "hal.h"
 #include "wolfboot/wolfboot.h"
-#include "update.c"
 
 #ifdef PLATFORM_stm32wb
 char enc_key[] = "0123456789abcdef0123456789abcdef" /* ChaCha key (256 bit) */