Tests: set SSL_verify_mode explicitly.

As of IO::Socket::SSL 1.79 warning appear if SSL_verify_mode isn't
explicitly set.

ssl_sni.t

diff --git a/ssl_sni.t b/ssl_sni.t
index cd9521f..207c925 100644
--- a/ssl_sni.t
+++ b/ssl_sni.t
@@ -131,6 +131,7 @@
 			Proto => 'tcp',
 			PeerAddr => '127.0.0.1:8443',
 			SSL_hostname => $host,
+			SSL_verify_mode => IO::Socket::SSL::SSL_VERIFY_NONE(),
 			SSL_error_trap => sub { die $_[1] }
 		);
 		alarm(0);