Memory leak - doesn't recycle sessions

[davidread]

This shiny server doesn't have session recycling functionality, that you'd expect if it contained an actual web server. This means each new user session loads the app into memory afresh, so a memory leak.

The memory leak becomes a serious issue in the case that:

• the Shiny app loads into memory lots of data at load time
• health checks cause the app to be loaded frequently

[davidread]

Use https://github.com/ministryofjustice/analytical-platform-rshiny-open-source-base instead