Fix type mismatch in error reporting

Author: raomin

src/esp32FOTA.cpp

@@ -564,7 +564,7 @@ bool esp32FOTA::execOTA( int partition, bool restart_after )
     }
 
     if (!F_UpdateEnd()) {
-        log_e("An Update Error Occurred. Error #: %s", F_Update.getError());
+        log_e("An Update Error Occurred. Error #: %d", F_Update.getError());
         return false;
     }