Updated gh-user-can-admin unit test

no issue
- helper now calls `.get('isOwnerOrAdmin')` rather than `.get('admin')` or `.get('owner')`

ghost/admin/tests/unit/helpers/gh-user-can-admin-test.js

@@ -4,29 +4,10 @@ import {ghUserCanAdmin} from 'ghost-admin/helpers/gh-user-can-admin';
 
 describe('Unit: Helper: gh-user-can-admin', function () {
     // Mock up roles and test for truthy
-    describe('Owner role', function () {
+    describe('Owner or admin roles', function () {
         let user = {
             get(role) {
-                if (role === 'isOwner') {
-                    return true;
-                } else if (role === 'isAdmin') {
-                    return false;
-                }
-            }
-        };
-
-        it(' - can be Admin', function () {
-            let result = ghUserCanAdmin([user]);
-            expect(result).to.equal(true);
-        });
-    });
-
-    describe('Administrator role', function () {
-        let user = {
-            get(role) {
-                if (role === 'isOwner') {
-                    return false;
-                } else if (role === 'isAdmin') {
+                if (role === 'isOwnerOrAdmin') {
                     return true;
                 }
             }