message: docs: add install step to migration guide
diff: @@ -110,14 +110,14 @@ export default {
  padding: 24px 0 0 var(--van-doc-padding);
  color: var(--van-doc-text-color-2);
  font-weight: 600;
  - font-size: 15px;
  + font-size: 16px;
  line-height: 28px;
  }
  &__item {
  a {
  display: block;
  - margin: 8px 0;
  + margin: 4px 0;
  padding: 6px 0 6px var(--van-doc-padding);
  color: var(--van-doc-text-color-3);
  font-size: 14px;
  