ngx-voms docker image

This commit introduces the ngx-voms docker image, and modifies the CI configuration to build the image.

docker/assets/srm.conf

@@ -31,6 +31,8 @@ server {
     proxy_set_header        X-Request-Id $request_id;
 
     # VOMS headers
+    proxy_set_header        x-ssl_client_ee_s_dn $ssl_client_ee_s_dn;
+    proxy_set_header        x-ssl_client_ee_i_dn $ssl_client_ee_i_dn;
     proxy_set_header        x-voms_fqans $voms_fqans;
     proxy_set_header        x-voms_user $voms_user;
     proxy_set_header        x-voms_user_ca $voms_user_ca;