Access Control - Infrastructure FrontEnd configuration

Configure the env variables for the FrontEnd:

NUXT_PUBLIC_KEYCLOAK_URL=https://auth-datamite-ds.iti.es
NUXT_PUBLIC_KEYCLOAK_REALM=datamite
NUXT_PUBLIC_KEYCLOAK_CLIENT_ID=datamite.user.interface

/cc @hugoloba , @edgarloba