Update the supported Streamlit version via the sdk_version metadata (#733)

Author: whitphx

docs/hub/spaces-config-reference.md

@@ -26,7 +26,7 @@ Defaults to `3.8.9`.
 **`sdk_version`** : _string_  
 Specify the version of the selected SDK (Streamlit or Gradio).  
 All versions of Gradio are supported.  
-Streamlit versions are supported from `0.79.0` to `1.15.2`.  
+Streamlit versions are supported from `0.79.0` to `1.19.0`.  
 
 **`app_file`** : _string_  
 Path to your main application file (which contains either `gradio` or `streamlit` Python code, or `static` html code).