redfish: Add AccountService Roles method test

Changes:
    - Added the test case:
    Verify AccountService Roles Unsupported Methods

Tested: Ran and Tested on BMC Environment
Change-Id: I1f63625e4b54e9b2493a0ee401a121030d5a24b8
Signed-off-by: Ian Lai <IanLai@ami.com>
diff --git a/redfish/account_service/test_user_account.robot b/redfish/account_service/test_user_account.robot
index 7d1503a..076b09d 100644
--- a/redfish/account_service/test_user_account.robot
+++ b/redfish/account_service/test_user_account.robot
@@ -579,6 +579,26 @@
     Redfish.Delete  /redfish/v1/AccountService
     ...  valid_status_codes=[${HTTP_METHOD_NOT_ALLOWED}]
 
+Verify AccountService Roles Unsupported Methods
+    [Documentation]  Verify Unsupported methods of AccountService/Roles
+    [Tags]  Verify_AccountService_Roles_Unsupported_Methods
+
+    # Put operation on Account Services Roles
+    Redfish.Put  /redfish/v1/AccountService/Roles
+    ...  valid_status_codes=[${HTTP_METHOD_NOT_ALLOWED}]
+
+    # Post operation on Account Services Roles
+    Redfish.Post  /redfish/v1/AccountService/Roles
+    ...  valid_status_codes=[${HTTP_METHOD_NOT_ALLOWED}]
+
+    # Delete operation on Account Services Roles
+    Redfish.Delete  /redfish/v1/AccountService/Roles
+    ...  valid_status_codes=[${HTTP_METHOD_NOT_ALLOWED}]
+
+    # Patch operation on Account Services Roles
+    Redfish.Patch  /redfish/v1/AccountService/Roles
+    ...  valid_status_codes=[${HTTP_METHOD_NOT_ALLOWED}]
+
 
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