Fixed specificity issue with admonitions in lists (#3648)

* Remove :is from .md-typeset (ol, ul) li :is(p, blockquote)

Fixes #3644

* Fix SCSS style

Author: iBug

src/assets/stylesheets/main/_typeset.scss

@@ -361,7 +361,8 @@ kbd {
       margin-inline-start: px2em(20px);
 
       // Adjust spacing
-      :is(p, blockquote) {
+      p,
+      blockquote {
         margin: 0.5em 0;
       }