I'm running fish 4.0b1 locally and I tried running `help abbr` and
browsing the docs. I noticed one example which wasn't formatted
correctly.
I'm not too familiar with rst, but based on looking at the file, it
seems that this is how example code should be represented.
(cherry picked from commit d47a4899b4179addaedd73f18cc1219bb6d9564a)