Cypress needs to be moved to the instance user

If you run the following on an out-of-the-box ktd:

ktd up -d
ktd --shell
yarn cypress run --env KOHA_USER=$KOHA_USER,KOHA_PASS=$KOHA_PASS

you get a message about needing to run cypress install. This is due to the fact some things get installed in /root/.cache during the Docker images build. This dirs/files need to be moved to the instance user on startup (i.e. when we know the instance name and the UID).