Fix parent and linked items widgets queries for group work items

What does this MR do and why?

Fix parent and linked items widgets queries for group work items

This is part of viewing work items at the group-level (#393240 (closed))

Behind feature flag namespace_level_work_items

Screenshots or screen recordings

Before	After
Screen_Recording_2023-10-30_at_3.56.52_pm	Screen_Recording_2023-10-30_at_3.59.11_pm

How to set up and validate locally

1. Apply diff to show parent widget

   diff --git a/app/assets/javascripts/work_items/components/work_item_attributes_wrapper.vue b/app/assets/javascripts/work_items/components/work_item_attributes_wrapper.vue
   index 7d09a003926e..c25f94a659dd 100644
   --- a/app/assets/javascripts/work_items/components/work_item_attributes_wrapper.vue
   +++ b/app/assets/javascripts/work_items/components/work_item_attributes_wrapper.vue
   @@ -195,7 +195,7 @@ export default {
          @error="$emit('error', $event)"
        />
        <work-item-parent
   -      v-if="showWorkItemParent"
   +      v-if="showWorkItemParent || true"
          class="gl-mb-5"
          :can-update="canUpdate"
          :work-item-id="workItem.id"

2. In rails console

   Feature.enable(:namespace_level_work_items)

3. Visit any work items list page for a paid subscription group such as http://127.0.0.1:3000/groups/flightjs/-/work_items
4. Create an epic
5. Confirm you can search for work items to add in the linked items widget and parent widget

MR acceptance checklist

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• I have evaluated the MR acceptance checklist for this MR.