Update CloudFront's upstream ECC Preference list

- from s2n_ecc_pref_list_20140601 to s2n_ecc_pref_list_20230623
  to include X25519 inline with CloudFront's documentation
  in https://docs.aws.amazon.com/AmazonCloudFront/latest/DeveloperGuide/secure-connections-supported-ciphers-cloudfront-to-origin.html

tls/s2n_security_policies.c

@@ -180,31 +180,31 @@ const struct s2n_security_policy security_policy_cloudfront_upstream = {
     .cipher_preferences = &cipher_preferences_cloudfront_upstream,
     .kem_preferences = &kem_preferences_null,
     .signature_preferences = &s2n_signature_preferences_20140601,
-    .ecc_preferences = &s2n_ecc_preferences_20140601,
+    .ecc_preferences = &s2n_ecc_preferences_20230623,
 };
 
 const struct s2n_security_policy security_policy_cloudfront_upstream_tls10 = {
     .minimum_protocol_version = S2N_TLS10,
     .cipher_preferences = &cipher_preferences_cloudfront_upstream_tls10,
     .kem_preferences = &kem_preferences_null,
     .signature_preferences = &s2n_signature_preferences_20140601,
-    .ecc_preferences = &s2n_ecc_preferences_20140601,
+    .ecc_preferences = &s2n_ecc_preferences_20230623,
 };
 
 const struct s2n_security_policy security_policy_cloudfront_upstream_tls11 = {
     .minimum_protocol_version = S2N_TLS11,
     .cipher_preferences = &cipher_preferences_cloudfront_upstream_tls11,
     .kem_preferences = &kem_preferences_null,
     .signature_preferences = &s2n_signature_preferences_20140601,
-    .ecc_preferences = &s2n_ecc_preferences_20140601,
+    .ecc_preferences = &s2n_ecc_preferences_20230623,
 };
 
 const struct s2n_security_policy security_policy_cloudfront_upstream_tls12 = {
     .minimum_protocol_version = S2N_TLS12,
     .cipher_preferences = &cipher_preferences_cloudfront_upstream_tls12,
     .kem_preferences = &kem_preferences_null,
     .signature_preferences = &s2n_signature_preferences_20140601,
-    .ecc_preferences = &s2n_ecc_preferences_20140601,
+    .ecc_preferences = &s2n_ecc_preferences_20230623,
 };
 
 /* CloudFront viewer facing */