Update HTC doc for using lcg-infosites instead of lcg-info which has been archived.

https://github.com/EGI-Federation/lcg-info got archived, we won't release it anymore, but we will package https://github.com/EGI-Federation/lcg-infosites. (still only supporting GLUE 1 for now).

We should update HTC doc for using lcg-infosites instead of lcg-info which has been archived.

https://docs.egi.eu/users/compute/high-throughput-compute/querying-information-system/#using-legacy-tools-for-glue-13 (and any possible other references)