Various minor fixes
This MR contains a few fixes for problems I found locally while building the documentation. I started this work because I wanted to fix a minor formatting issue (2ba1e9b7), but found a few warnings when building the docs locally so I went and fixed those as well. See individual commits for details.
I also included a change to treat warnings as errors on the CI pipeline to prevent further warnings from creeping in.
Edited by Rodrigo Tobar