fix IDC Swagger URL

Author: fedorov

API/notebooks/How_to_use_IDC_APIs.ipynb

@@ -94,7 +94,7 @@
       "source": [
         "### What is SwaggerUI?\n",
         "\n",
-        "[SwaggerUI](https://swagger.io/tools/swagger-ui/) is a user interface that allows users to try out the APIs and view their documentation easily. You can access the IDC API SwaggerUI [here](https://api-dot-idc-dev.appspot.com/v1/swagger)."
+        "[SwaggerUI](https://swagger.io/tools/swagger-ui/) is a user interface that allows users to try out the APIs and view their documentation easily. You can access the IDC API SwaggerUI [here](https://api.imaging.datacommons.cancer.gov/v1/swagger)."
       ]
     },
     {
@@ -1092,4 +1092,4 @@
       "outputs": []
     }
   ]
-}
+}