chore(docs): Updated API Reference (automated) (#10017)

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

Co-authored-by: Oli Juhl <59018053+olivermrbl@users.noreply.github.com>
Co-authored-by: Shahed Nasser <27354907+shahednasser@users.noreply.github.com>

www/apps/api-reference/specs/admin/paths/admin_customers_{id}_customer-groups.yaml

@@ -12,10 +12,13 @@ post:
         type: string
     - name: fields
       in: query
-      description: |-
+      description: >-
         Comma-separated fields that should be included in the returned data.
-         * if a field is prefixed with `+` it will be added to the default fields, using `-` will remove it from the default fields.
-         * without prefix it will replace the entire default fields.
+
+        if a field is prefixed with `+` it will be added to the default fields,
+        using `-` will remove it from the default fields.
+
+        without prefix it will replace the entire default fields.
       required: false
       schema:
         type: string