Update libraries/WiFi/extra/README.md

Co-authored-by: per1234 <[email protected]>

Author: facchinm

libraries/WiFi/extra/README.md

@@ -6,7 +6,7 @@ cd esp-hosted/
 patch -p1 < ../0001-Defaults-for-C33-BLE.patch
 cd esp_hosted_fg/esp/esp_driver/
 ./esp-idf/install.sh esp32s3
-. esp-idf/export.sh
+. ./esp-idf/export.sh
 cd network_adapter/
 idf.py set-target esp32c3
 cp ../../../../../sdkconfig.default.c33 sdkconfig