ISTWCMS-4199: fixing header menu links

source/_patterns/04-components/menu/menu--header/menu--header.twig

 {% set submenu = [] %}
 
-{% set submenu = submenu|merge
-  (
+{% set submenu = submenu|merge([
   {
     'title': 'Admissions',
     'url': 'https://uwaterloo.ca/admissions/',
     'in_active_trail': false
-  }
-  )
-%}
-
-{% set submenu = submenu|merge
-  (
+  },
   {
     'title': 'About Waterloo',
     'url': 'https://uwaterloo.ca/about/',
     'in_active_trail': false
-  }
-  )
-%}
-
-{% set submenu = submenu|merge
-  (
+  },
   {
     'title': 'Faculties & Academics',
     'url': 'https://uwaterloo.ca/faculties-academics/',
     'in_active_trail': false
-  }
-  )
-%}
-
-{% set submenu = submenu|merge
-  (
+  },
   {
     'title': 'Offices & Services',
     'url': 'https://uwaterloo.ca/offices-services/',
     'in_active_trail': false
-  }
-  )
-%}
-
-{% set submenu = submenu|merge
-  (
+  },
   {
     'title': 'Support Waterloo',
     'url': 'https://uwaterloo.ca/support/',
     'in_active_trail': false
-  },
-  )
-%}
-{% set items = [] %}
-{% set items = items|merge({'title': 'Jump to', 'url': '#', 'in_active_trail': 'false', 'submenu': submenu}) %}
-
+  }
+]) %}
 
+{% set items = [] %}
+{% set items = items|merge([
+  {
+    'title': 'Jump to',
+    'url': '#',
+    'in_active_trail': 'false',
+    'submenu': submenu
+  }
+]) %}
 
 <div class="uw-header-menu" aria-label="">
   {% include "@components/menu/menu--horizontal/menu--horizontal.twig" with {
-    'items': items,
-    'is_demo': true
+    'items': items
   }%}
 </div>