Drop remark about anonymous ciphers

The documentation no longer mentions anonymous ciphers. They are totally
insecure and irrelevant for virtually all users. The documentation was
also wrong. For anonymous ciphers, CERT_NONE, CERT_OPTIONAL and
CERT_REQUIRED all behaved the same.

Internally, CERT_REQUIRED = SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT
but the last flag is ignored in client mode. When a anonymous cipher is
used, clients ignore missing server certs.

Signed-off-by: Christian Heimes <[email protected]>

Author: tiran

Doc/library/ssl.rst

@@ -2553,11 +2553,6 @@ In server mode, if you want to authenticate your clients using the SSL layer
 (rather than using a higher-level authentication mechanism), you'll also have
 to specify :const:`CERT_REQUIRED` and similarly check the client certificate.
 
-   .. note::
-
-      In client mode, :const:`CERT_OPTIONAL` and :const:`CERT_REQUIRED` are
-      equivalent unless anonymous ciphers are enabled (they are disabled
-      by default).
 
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