Added the error coverage for category query (#8489)

* Added the error coverage for category query

* made the suggested changes

Co-authored-by: Dinesh V B <dbabu@ztech.io>
Co-authored-by: Kevin Harper <keharper@users.noreply.github.com>

Author: 3 people

src/guides/v2.3/graphql/queries/category.md

@@ -212,3 +212,10 @@ The query returns a `CategoryTree` object, which implements [`CategoryInterface`
 Attribute | Data type | Description
 --- | --- | ---
 `children` | `CategoryTree` | An array containing the next level of subcategories. By default, you can specify up to 10 levels of child categories
+
+## Errors
+
+Error | Description
+--- | ---
+`Category doesn't exist` | The specified category ID value does not exist.
+`Field "category" argument "id" requires type Int, found "XXX"` | The specified `id` argument value has the wrong type.

src/guides/v2.4/graphql/queries/category.md

@@ -210,3 +210,10 @@ The query returns a `CategoryTree` object, which implements [`CategoryInterface`
 Attribute | Data type | Description
 --- | --- | ---
 `children` | `CategoryTree` | An array containing the next level of subcategories. By default, you can specify up to 10 levels of child categories
+
+## Errors
+
+Error | Description
+--- | ---
+`Category doesn't exist` | The specified category ID value does not exist.
+`Field "category" argument "id" requires type Int, found "XXX"` | The specified `id` argument value has the wrong type.