Add `display: block` to host mixin

[luke-m]

Is your feature request related to a problem? Please describe.
As of now, a bioElement that uses the host mixin doesn't have display: block which leads to the element not showing up properly when inspected in chrome DEV tools.

Describe the solution you'd like
Add display: block to the host mixin.

Additional context
Without display: block

With display: block

[SheepFromHeaven]

@luke-m I would prefer to add it to the generator and let the host mixin do what it does

[luke-m]

Fine for me either way.