It turns out that we missed part of the OSC 8 spec which indicated that
_hyperlinks with the same ID but different URIs are logically distinct._
> Character cells that have the same target URI and the same nonempty id
> are always underlined together on mouseover.
> The same id is only used for connecting character cells whose URIs is
> also the same. Character cells pointing to different URIs should never
> be underlined together when hovering over.
This pull request fixes that oversight by appending the (hashed) URI to
the generated ID.
When Terminal receives one of these links over ConPTY, it will hash the
URL a second time and therefore append a second hashed ID. This is taken
as an acceptable cost.
Fixes#7698
df7c3ccc3b