Fix test to work on prove -lr

[ribasushi]

The way prove -lr works you could end up with a "fuller" relative path:

rabbit@Ahasver:~/devel/dbic$ cpanm --look DBIx::Class::Candy
--> Working on DBIx::Class::Candy
Fetching http://www.cpan.org/authors/id/F/FR/FREW/DBIx-Class-Candy-0.005001.tar.gz ... OK
Entering /home/rabbit/.cpanm/work/1461929910.16724/DBIx-Class-Candy-0.005001 with /bin/bash

rabbit@Ahasver:~/.cpanm/work/1461929910.16724/DBIx-Class-Candy-0.005001$ prove -lr
./t/autotable.t .................... 
    #   Failed test 'unknown naming scheme'
    #   at ./t/autotable.t line 32.
    #                   'unrecognized naming scheme! at ./t/autotable.t line 30.
    # '
    #     doesn't match '(?^:^unrecognized naming scheme! at t[\\/]autotable\.t)'
    # Looks like you failed 1 test of 4.
./t/autotable.t .................... 1/? 
#   Failed test 'v1'
#   at ./t/autotable.t line 35.
# Looks like you failed 1 test of 2.
./t/autotable.t .................... Dubious, test returned 1 (wstat 256, 0x100)
Failed 1/2 subtests 
...

Also the lack of /s on the regex may trip you up on certain
"always stacktrace" environments, but that's sufficiently esoteric
that I didn't bother adding it.

[coveralls]

Coverage remained the same at 95.662% when pulling aa5927c on ribasushi:patch-1 into 6a4c248 on frioux:master.