make Test::Taint a normal prereq

Don't allow tests to pass when prereqs are missing.

Author: haarg

dist.ini

@@ -30,7 +30,6 @@ Scalar::Util = 1.14
 [Prereqs / TestRequires]
 HTTP::Daemon = 6.12
 Test::Memory::Cycle = 1.06
-Test::Taint = 1.08
 
 [Prereqs / DevelopRequires]
 LWP::Protocol::https = 6.07

t/taint.t

@@ -2,13 +2,8 @@
 
 use warnings;
 use strict;
-use Test::More;
-
-BEGIN {
-    eval 'use Test::Taint';
-    plan skip_all => 'Test::Taint required for checking taintedness' if $@;
-    plan tests=>6;
-}
+use Test::More tests => 6;
+use Test::Taint 1.08;
 
 BEGIN {
     use_ok( 'WWW::Mechanize' );