Ensure unsupported ranges do not trigger

lib/DDG/Goodie/RandomDate.pm

@@ -77,6 +77,7 @@ handle query => sub {
         $force_cldr = defined $+{cldr};
     }
     srand();
+    return if $range_text && $range_type eq 'none';
     my ($min_date, $max_date) = parse_range($range_type, $lang->locale, $range_text);
     return if $range_text && !(defined $min_date && defined $max_date);
     my $random_date = get_random_date($lang->locale, $min_date, $max_date);

t/RandomDate.t

@@ -180,6 +180,8 @@ ddg_goodie_test(
     ),
     'random date between'             => undef,
     'random date between now and bar' => undef,
+    # Not supported
+    'random century in the past' => undef,
     # Invalid Queries
     'date for %K'         => undef,
     'date for %{year}'    => undef,