Our previous implementation used a simple `blocked_domain_array.include?(hostname)`
so some values were not matching. Additionally, in some configurations like ours, we'd used
"cat.*.dog.com" with the assumption we'd support globbing.
This change implicitly allows globbing by blocking "http://a.b.com" if "b.com" is a blocked
domain but does not actively do anything for "*".
An upcoming change might include frontend validation for values that can be inserted.