Automatically add `objects.txt` to site resources

[gadenbuie]

It'd be super helpful if the interlinks extension added objects.txt to the site resources, rather than requiring it to be manually added:

quartodoc/docs/_quarto.yml

Lines 4 to 8 in 8d7ade2

	resources:
	- examples/single-page
	- examples/pkgdown
	- examples/auto-package
	- objects.txt

I'm not 100% sure that there's an easy way to do that in Quarto, though. If not, it'd be helpful to include that step in the instructions here https://machow.github.io/quartodoc/get-started/interlinks.html.