Cleanup hardcoded cipher suite codepoints in s_server

The hardcoded code points for TLSv1.3 cipher suites are used in the TLS
PSK server callback. However, they seem to have been refactored a while
ago to use tls13_aes128gcmsha256_id, so these defines are not necessary
within the s_server code anymore.
Reviewed-by: NRichard Levitte <levitte@openssl.org>
Reviewed-by: NMatt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/10243)

(cherry picked from commit aed8c47cbcc8a289bea433ead2effea035187260)

apps/s_server.c

@@ -180,9 +180,6 @@ static unsigned int psk_server_cb(SSL *ssl, const char *identity,
 }
 #endif
 
-#define TLS13_AES_128_GCM_SHA256_BYTES  ((const unsigned char *)"\x13\x01")
-#define TLS13_AES_256_GCM_SHA384_BYTES  ((const unsigned char *)"\x13\x02")
-
 static int psk_find_session_cb(SSL *ssl, const unsigned char *identity,
                                size_t identity_len, SSL_SESSION **sess)
 {