DOC: Fix formatting of sequences.md

[lassoan]

No description provided.

[jamesobutler]

@lassoan Not sure if you've already identified this but the bullet points in the documentation stopped being displayed properly seemingly first with PR (completed June 11 3:32 PM) https://readthedocs.org/projects/slicer/builds/13988267/.

The previous build from a PR (completed June 11 2:48 PM) showed it correctly https://readthedocs.org/projects/slicer/builds/13987860/.

I found this by reviewing the builds https://readthedocs.org/projects/slicer/builds/.

Maybe something updated with the build tools around 2:48 PM to 3:32 PM that introduced the bullet points issue? The changes in the PR where it was first observed as being wrong should not have changed anything about how the documentation is built.

[lassoan]

Thanks for reporting. I've noticed this, too. I though that I messed up something. I had a lot of trouble reproducing the issue locally (I had to install linux and set up a docker container to fully reproduce readthedocs software stack, etc.) then figure out what was wrong. As it turned out, readthedocs and docutils messed this up big time for everyone (!) using readthedocs default theme. The workaround in the end was very simple - to force update to the default readthedocs theme that is compatible with the default docutils version (48f6071). It was really frustrating, I wasted about 8 hours with this.