Remove fairsale from MVP release branch and subgraph deployment

[rossneilson]

After we merge into main and cut a release branch for the fixed price MVP release we should merge a feature branch to remove the fairsale page from routing as well as from sale summary cards on the /sales page.
Of course we wont be launching fairsales ourselves on the production contracts, however if one is launched accidentally then we need to make sure it doesnt appear to users in production who may be confused or even try to take part in the sale.
Subgraph also needs this removed to prevent crashing that happens when launching sales. During this the subgraph endpoint should be updated to just aqua-xdai (not -next)