Tezt/Cloud/DAL: Clean Explorus appearing twice on the website

What

Remove duplicate of Explorus link appearing on the website.

Why

Because a few line above deleted paragraph, there is a call to init_explorus which already add a link to the website.

Manually testing the MR

Launch any experiment with --website and the link to Explorus should appear only once.

Example:

make && dune exec tezt/tests/cloud/main.exe -- DAL -v --website --grafana --log-file /tmp/log_$(date "+%Hh%M") --producers 1 --tezt-cloud guillaumeg --dockerfile-alias dal --stake 2,2