docs: fix typo in `authoring content.md` (#408)

Ben Schlegel

2023-08-24 9d2340e90b55fb9480e0901bc7360f3d72e688da

 quartz/styles/callouts.scss

@@ -7,6 +7,7 @@
  padding: 0 1rem;
  overflow-y: hidden;
  transition: max-height 0.3s ease;
  box-sizing: border-box;

  & > *:nth-child(2) {
    margin-top: 0;