fix: add use 5.010 to all test files for Perl 5.8.x protection

t/0use.t

@@ -1,3 +1,4 @@
+use 5.010;
 use strict;
 use warnings;
 use Test::More tests => 1;

t/apache.t

@@ -1,5 +1,6 @@
 # $Id: apache.t,v 1.28 1999/08/26 23:39:52 john Exp $
 
+use 5.010;
 use strict;
 use warnings;
 

t/export.t

@@ -4,6 +4,7 @@
 # These test the rarely-exercised Exporter extension that makes
 # "use Net::Ident ':fh'" add methods to other packages.
 
+use 5.010;
 use strict;
 use warnings;
 use Test::More;