fix(wifi): Free scan configuration after use when channel bitmap is used

examples/wifi/scan/main/scan.c

@@ -179,6 +179,7 @@ static void wifi_scan(void)
     }
     array_2_channel_bitmap(channel_list, CHANNEL_LIST_SIZE, scan_config);
     esp_wifi_scan_start(scan_config, true);
+    free(scan_config);
 
 #else
     esp_wifi_scan_start(NULL, true);