TypelevelSitePlugin assumes site is in a directory called docs

[rossabaker]

https://github.com/typelevel/cats-uri/runs/4909193164?check_suite_focus=true#step:5:30

[armanbilge]

Oh yeah, those may be baked in a little too hard. I just followed the instructions for mdoc.

lazy val docs = project       // new documentation project
  .in(file("myproject-docs")) // important: it must not be docs/
  .dependsOn(myproject)
  .enablePlugins(MdocPlugin)

Next, from the sbt shell, run the docs/mdoc task to generate the documentation site. By default, the mdoc task looks for markdown sources in the toplevel docs/ directory.

https://scalameta.org/mdoc/docs/installation.html#sbt