Tests: fixed ssl_stapling.t for nginx built with OpenSSL 0.9.8y+.

OpenSSL 0.9.8 covers ECC-based ciphersuites under pre-RFC4492 "ECCdraft" alias.
diff --git a/ssl_stapling.t b/ssl_stapling.t
index fd9e701..9319fbe 100644
--- a/ssl_stapling.t
+++ b/ssl_stapling.t
@@ -59,6 +59,8 @@
     ssl_certificate end-int.crt;
     ssl_certificate_key end.key;
 
+    ssl_ciphers DEFAULT:ECCdraft;
+
     server {
         listen       127.0.0.1:8443 ssl;
         listen       127.0.0.1:8080;