Add example on how to use Snowflake Reference secret within native app

[nipunj15]

Please add examples on how to use References for accessing Snowflake secrets within the native app. This is often needed for integrating with external APIs which requires some sort of API key. Not clear from the documentation on how to access secrete references within the streamlit app

[nipunj15]

The above is a blocker for a native app that we're building. Would be great if the team can prioritise this or even give some direction on this issue itself @sfc-gh-osalazarlizano