Replace CSP plugin-types directive with object-src

The HTTP Content-Security-Policy (CSP) plugin-types directive has been
marked as deprecated and suggests set object-src none to disallow
plugins.

Signed-off-by: Brian Ma <chma0@nuvoton.com>
Change-Id: Ie532deeb8d8cb0d1de275b5d864bd20dc5f11ce7
diff --git a/redfish/service_root/test_service_root_security.robot b/redfish/service_root/test_service_root_security.robot
index 4640ecf..c0a8d89 100644
--- a/redfish/service_root/test_service_root_security.robot
+++ b/redfish/service_root/test_service_root_security.robot
@@ -16,7 +16,7 @@
 ...                     X-Frame-Options=DENY
 ...                     Pragma=no-cache
 ...                     Cache-Control=no-Store,no-Cache
-...                     Content-Security-Policy=default-src 'none'; img-src 'self' data:; font-src 'self'; style-src 'self'; script-src 'self'; connect-src 'self' wss:; form-action 'none'; frame-ancestors 'none'; plugin-types 'none'; base-uri 'none'
+...                     Content-Security-Policy=default-src 'none'; img-src 'self' data:; font-src 'self'; style-src 'self'; script-src 'self'; connect-src 'self' wss:; form-action 'none'; frame-ancestors 'none'; object-src 'none'; base-uri 'none'
 ...                     X-XSS-Protection=1; mode=block
 ...                     X-Content-Type-Options=nosniff