Use of deprecated shiny::dataTableOutput()

[SHorschBay]

Starting the app with current packages leads to the following warning:

shiny::dataTableOutput() is deprecated as of shiny 1.8.1.
Please use DT::DTOutput() instead.
Since you have a suitable version of DT (>= v0.32.1), shiny::dataTableOutput() will automatically use DT::DTOutput() under-the-hood.
If this happens to break your app, set options(shiny.legacy.datatable = TRUE) to get the legacy datatable implementation (or FALSE to squelch this message).
See https://rstudio.github.io/DT/shiny.html for more information.

Replace occurences of shiny::dataTableOutput() with DT::DTOutput().

[SHorschBay]

Occurs only in create-file-tab branch, is already addressed by commit 7b3ae0d