When kableExtra loads, it calls this function if it
detects that knitr is running and producing
LaTeX output. However, sometimes kableExtra
is loaded before knitr runs, and then these packages
can end up being missed, leading to LaTeX errors such as
"Undefined control sequence." (See
Github issue #721 for an example.)
Our kbl() wrapper for knitr::kable() calls
this function for LaTeX output, so an explicit call
is not necessary.