Fix display of features in rustdoc

Author: GuillaumeGomez

src/librustdoc/html/static/css/rustdoc.css

@@ -1081,15 +1081,9 @@ so that we can apply CSS-filters to change the arrow color in themes */
 }
 
 .item-info .stab {
-	/* This min-height is needed to unify the height of the stab elements because some of them
-	   have emojis.
-	*/
-	min-height: 36px;
-	display: flex;
+	display: block;
 	padding: 3px;
 	margin-bottom: 5px;
-	align-items: center;
-	vertical-align: text-bottom;
 }
 .item-name .stab {
 	margin-left: 0.3125em;
@@ -1104,7 +1098,6 @@ so that we can apply CSS-filters to change the arrow color in themes */
 	white-space: pre-wrap;
 	border-radius: 3px;
 	display: inline;
-	vertical-align: baseline;
 }
 
 .stab.portability > code {