Fix 3 tests which fail with icu-4.6
Fix 3 tests which fail with icu-4.6

This originally tested that an undefined codepoint matched <!isAlphabetic>, but
as of Unicode 6.0 it's defined *and* part of an alphabet. Replaced it with a
defined punctuation codepoint.

dankogai/roast,niner/roast,bitrauser/roast,niner/roast,laben/roast,zostay/roast,dankogai/roast,b2gills/roast,perl6/roast,niner/roast,laben/roast,zostay/roast,bitrauser/roast,dogbert17/roast,b2gills/roast,laben/roast,cygx/roast,skids/roast,b2gills/roast,cygx/roast,skids/roast,skids/roast,dankogai/roast,cygx/roast,zostay/roast,dogbert17/roast