Fixed description and link for Endpoint services in definition.mdx (#…

…2806)

* Fixed description and link for Endpoint services in definition.mdx

* Update Services to Endpoints in definition.mdx

fern/docs/pages/fern-definition/definition.mdx

@@ -3,7 +3,7 @@ A Fern Definition is a set of YAML files that describe your API.
 Each **Fern Definition** file may define:
 
 - **[Custom types](/api-definition/fern-definition/types)**. Use **custom types** to build your data model.
-- **[Services](/api-definition/fern-definition/services)**. A **service** is a set of related REST endpoints.
+- **[Endpoints](/api-definition/fern-definition/endpoints)**. Group related endpoints into **services**.
 - **[Errors](/api-definition/fern-definition/errors)**. An **error** represents a failed (non-200) response from an endpoint.
 
 ## An example of a Fern Definition