fix in DTOutput when using namespace

[jos4uke]

Hi @ColinFay

There is a missing namespace when accessing the return function "dt" from the server:

https://github.com/ColinFay/golemexamples/blob/46379d0cd9fc0a0bdef31257e94608faf78300b6/golemshinydash/R/mod_name_of_module2.R#L14

It should be:

DT::DTOutput(ns("dt")) 

Best regards