chore(docs): Updated API Reference (v2) (#9437)

Automated changes by [create-pull-request](https://github.com/peter-evans/create-pull-request) GitHub action

Co-authored-by: Shahed Nasser <27354907+shahednasser@users.noreply.github.com>

www/apps/api-reference/specs/admin/components/schemas/AdminCustomerGroup.yaml

@@ -2,9 +2,9 @@ type: object
 description: The customer group's details.
 x-schemaName: AdminCustomerGroup
 required:
+  - customers
   - id
   - name
-  - customers
   - metadata
   - created_at
   - updated_at
@@ -21,7 +21,7 @@ properties:
     type: array
     description: The customer group's customers.
     items:
-      $ref: ./BaseCustomer.yaml
+      type: object
   metadata:
     type: object
     description: The customer group's metadata, used to store custom key-value pairs.