test_ssl: fix ssl context protocol

tests/test_ssl.py

@@ -50,7 +50,7 @@ for s, d in conf_servers:
     try:
         # further tests
         conn = ssl.create_connection((v, 443))
-        context = ssl.SSLContext()
+        context = ssl.SSLContext(ssl.PROTOCOL_TLS)
         sock = context.wrap_socket(conn, server_hostname=v)
         cert = ssl.DER_cert_to_PEM_cert(sock.getpeercert(True))
         x509 = OpenSSL.crypto.load_certificate(OpenSSL.crypto.FILETYPE_PEM, cert)