The colon_fence myst extension enables triple-colon fences for
admonitions, as in:
:::{note}
**Regular** _markdown_ text, not code.
:::
Using triple colon fences for admonition blocks helps markdown editors
treat the body as markdown text, rather than fixed-width code with a
syntax highlight.
This change fixes a live doc bug in MyFirstTypoFix.md, which uses this
admonition style:
https://llvm.org/docs/MyFirstTypoFix.html
Currently ":::{note} The code changes presented" leaks through in the
HTML, and this one line change fixes it.
Reid Kleckner
69e2ec6e7c