alias collisions test fix

the output code for aliases does correctly install aliases in a position
relative to the page if the output path provided is relative, but until
the last commit we would not do this correctly when collectiong path
information to detect collisions. the last commit put both systems
in sync but I forgot to update the corresponding snapshot test

Author: kristoff-it

tests/content-scanning/collisions/snapshot.txt

@@ -59,14 +59,6 @@ another_index.html: error: output url collision detected
    between  index.smd (page alias)
    and      nested/path/page.smd (page alias)
 
-foo/bar/baz.html: error: output url collision detected
-   between  index.smd (page alias)
-   and      nested/path/page.smd (page alias)
-
-foo/bar.html: error: output url collision detected
-   between  index.smd (page alias)
-   and      nested/path/page.smd (page alias)
-
 nested/path/page/README.html: error: output url collision detected
    between  index.smd (page alternative 'readme')
    and      nested/path/page.smd (page alternative 'readme')