fix: Corrected schema link in model_runtime's README.md (#4757)

api/core/model_runtime/README.md

 
   ![image-20231210143654461](./docs/en_US/images/index/image-20231210143654461.png)
 
-  Displays a list of all supported providers, including provider names, icons, supported model types list, predefined model list, configuration method, and credentials form rules, etc. For detailed rule design, see: [Schema](./schema.md).
+  Displays a list of all supported providers, including provider names, icons, supported model types list, predefined model list, configuration method, and credentials form rules, etc. For detailed rule design, see: [Schema](./docs/en_US/schema.md).
 
 - Selectable model list display