add a link that leads to a list of synapse entities

Author: linglp

docs/tutorials/python/json_schema.md

@@ -1,4 +1,4 @@
-JSON Schema is a tool used to validate data. In Synapse, JSON Schemas can be used to validate the metadata applied to a project, file, folder, table, or view, including the [annotations](https://help.synapse.org/docs/Annotating-Data-With-Metadata.2667708522.html) applied to it. To learn more about JSON Schemas, check out [JSON-Schema.org](https://json-schema.org./).
+JSON Schema is a tool used to validate data. In Synapse, JSON Schemas can be used to validate the metadata applied to an entity such as project, file, folder, table, or view, including the [annotations](https://help.synapse.org/docs/Annotating-Data-With-Metadata.2667708522.html) applied to it. To learn more about JSON Schemas, check out [JSON-Schema.org](https://json-schema.org/). You can view a full list of entities supported by Synapse [here](https://rest-docs.synapse.org/rest/index.html#org.sagebionetworks.repo.web.controller.EntityController)
 
 Synapse supports a subset of features from [json-schema-draft-07](https://json-schema.org/draft-07). To see the list of features currently supported, see the [JSON Schema object definition](https://rest-docs.synapse.org/rest/org/sagebionetworks/repo/model/schema/JsonSchema.html) from Synapse's REST API Documentation