Add "permanent lease" for GPU

[pierrelefevre]

Some VMs need permanent GPUs, let's add a way to do this in the admin panel so we don't have to edit the database.

@saffronjam guessing you need to add a route for this, admin only of course

[pierrelefevre]

add {noLeaseEnd: true} to attach GPU call body - add toggle button when leasing GPU for admins only for Infinite lease.