Removed default Elliptic Curve Cryptography Public Key Algorithm for nginx

  In case `ssl_ecdh_curve` option un-defined explicitly, nginx
  sets option to `auto` mode. It allows auto-negotiation
  ECC between client and server.
  According to http://nginx.org/en/docs/http/ngx_http_ssl_module.html#ssl_ecdh_curve

  It needed because chromium based browsers un-support
  secp521r1 Elliptic Curve Cryptography Public Key Algorithm.

Related-PROD: PROD-30636

Change-Id: If19d7eedc49a119b064def0b77f1024e2add7d6a
diff --git a/nginx/server/proxy/ssl.yml b/nginx/server/proxy/ssl.yml
index dd4f2cd..fdd95a5 100644
--- a/nginx/server/proxy/ssl.yml
+++ b/nginx/server/proxy/ssl.yml
@@ -8,10 +8,6 @@
       dhparam:
         enabled: True
         numbits: 2048
-      ecdh_curve:
-        secp521r1:
-          name: 'secp521r1'
-          enabled: True
       prefer_server_ciphers: "on"
       protocols:
         TLSv1: