Fix dracula's theme list-style on sub-items

dist/theme/dracula.css

@@ -382,7 +382,7 @@ section.has-light-background, section.has-light-background h1, section.has-light
   color: var(--r-inline-code-color);
 }
 
-.reveal ul {
+.reveal ul li {
   list-style: none;
 }
 
@@ -411,4 +411,4 @@ section.has-light-background, section.has-light-background h1, section.has-light
 
 .reveal ol li {
   counter-increment: li;
-}
+}