Composer command for getting ECA library are not the right one

Thanks a lot @n.dhuygelaere for reporting this. The commands are correct on packagist.org and also on https://gitlab.lakedrops.com/drupal/recipes where the source of the recipes currently lives. Only the templates for the ECA Guide are using the wrong ID. I'll fix that right away.

The ECA Guide is now corrected as well.