Rename test directories

These names don't make sense now that we run both suites the same
way.

hphp/test/quick/lexer_heredoc_var_newlines.php

@@ -6,7 +6,7 @@ $info
 throw new Exception(<<<TXT
 $info
 
-Fix the above
+Fix the above and then run `arc build`
 TXT
 );
 SCRIPT;

hphp/test/quick/lexer_heredoc_var_newlines.php.expect

@@ -3,6 +3,6 @@ hello
 throw new Exception(<<<TXT
 hello
 
-Fix the above
+Fix the above and then run `arc build`
 TXT
 );