Use recipe:: prefix to build name

minitest-chef-handler builds the full recipe name using a 'recipe::'
prefix. This full name is then matched against the minitest filter
shared between this cookbook and the minitest library itself. However,
the minitest library has the full name including recipe::, and requires
the filter to allow for that.

To permit the files to be copied at all so minitest sees them, let alone
filters them properly, matches_filter? must also use the name including
'recipe::'.

An alternative to this would be to modify minitest-chef-handler, or rely
on its filtering routines instead of reimplementing them, to ensure
consistency. This is the quick fix that we've got in place while we
figure out what the right thing to do is.