Should not default to including fontspec just because `is_quarto` is true

[jflournoy]

flextable/R/latex_str.R

Lines 46 to 48 in 91eef94

	if (fontspec_compat || is_quarto) {
	x$fontspec <- latex_dependency("fontspec")
	}

This may be a niche issue, but I'm compiling for arXiv submission and I need to ensure that it compiles with pdflatex and thus doesn't include the fontspec package. I can get most of the way their with the flextable::set_flextable_defaults(fonts_ignore = TRUE), but when compiling with pdf-engine: pdflatex in the _quarto.yaml I still get fontspec included.

Thanks!