[PATCH 3 of 6] Tests: unbreak stream_ssl_variables.t with old IO::Socket::SSL

[Sergey Kandaurov]

# HG changeset patch
# User Sergey Kandaurov <pluknet at nginx.com>
# Date 1684773874 -14400
#      Mon May 22 20:44:34 2023 +0400
# Node ID e60c76cbf2a5b0d9e1d235770d68f260cf1a4e3e
# Parent  4a3a451716ba26f8fc4be1ccc88dd8596101a6b2
Tests: unbreak stream_ssl_variables.t with old IO::Socket::SSL.

Do not clobber a stream object in test_tls13().

diff --git a/stream_ssl_variables.t b/stream_ssl_variables.t
--- a/stream_ssl_variables.t
+++ b/stream_ssl_variables.t
@@ -141,7 +141,7 @@ undef $s;
 ###############################################################################
 
 sub test_tls13 {
-	$s = stream(PeerAddr => '127.0.0.1:' . port(8443), SSL => 1);
+	my $s = stream(PeerAddr => '127.0.0.1:' . port(8443), SSL => 1);
 	$s->read() =~ /TLSv1.3/;
 }