test: another line terminator bug fix
I believe this case is different from the last in that it happens when
the end of a *multi-line* annotation occurs after a line terminator.
Previously, the diagnostic would render on the next line, which is
definitely a bit weird. This new update renders it at the end of the
line the annotation ends on.
In some cases, the annotation was previously rendered to point at source
lines below where the error occurred, which is probably pretty
confusing.
