bpo-35031, test_asycio: disable TLS 1.3 in test_start_tls_server_1() (GH-14148)

bpo-35031, bpo-35998: Reintroduce workaround on Windows and FreeBSD
in test_start_tls_server_1() of test_asyncio: disable TLS v1.3 on the
client context.
(cherry picked from commit c034b78)

Co-authored-by: Victor Stinner <vstinner@redhat.com>

Author: miss-islington

Lib/test/test_asyncio/test_sslproto.py

@@ -495,6 +495,12 @@ def test_start_tls_server_1(self):
 
         server_context = test_utils.simple_server_sslcontext()
         client_context = test_utils.simple_client_sslcontext()
+        if sys.platform.startswith('freebsd') or sys.platform.startswith('win'):
+            # bpo-35031: Some FreeBSD and Windows buildbots fail to run this test
+            # as the eof was not being received by the server if the payload
+            # size is not big enough. This behaviour only appears if the
+            # client is using TLS1.3.
+            client_context.options |= ssl.OP_NO_TLSv1_3
         answer = None
 
         def client(sock, addr):