TESTSITE="http://<host>/downloads-path/" must be auto-indexed

[KsmoinO]

Hello

A note should be added to the readme to precise that the site pointed by TESTSITE must be auto-indexed (Ex: Apache option Indexes must be added to the directory) or at least display a link to the ${BOARD}-squashfs-sysupgrade.bin and the folder must also contains the sha256sums file

Regards

[darkxst]

Hi, feel free to make a PR to update the README with your suggested changes. Thanks