better diagnostics in case of failures in apache.t

Author: chorny

t/apache.t

@@ -8,11 +8,13 @@ use LWP::UserAgent;
 my $ua = LWP::UserAgent->new();
 plan skip_all => "Not online" unless $ua->is_online;
 
-plan tests => 4;
+plan tests => 5;
 
 my $res = $ua->simple_request(HTTP::Request->new(GET => "https://www.apache.org"));
 
 ok($res->is_success);
+my $h = $res->header( 'X-Died' );
+is($h, undef, "no X-Died header");
 like($res->content, qr/Apache Software Foundation/);
 
 # test for RT #81948