Make testing of path independent of absolute paths setup.
Make testing of path independent of absolute paths setup.

We can not assume that the full absolute path is the same
for the UpwardFileSearch() as it does realpath(). We only
know that 'our' part of the filesystem construction will
match.

Signed-off-by: Henner Zeller <259ad50fabbfd39355f36ecd6c0afca541ea66ef@acm.org>

chipsalliance/verible,chipsalliance/verible,chipsalliance/verible,chipsalliance/verible,chipsalliance/verible