Switch Mermaid scrollbar to automatic

Author: Tim Bannister

assets/scss/_custom.scss

@@ -64,7 +64,7 @@ body.td-404 main .error-details {
 /* Global - Mermaid.js diagrams */
 
 .mermaid {
-  overflow: scroll;
+  overflow-x: auto;
   max-width: 80%;
   border: 1px solid rgb(222, 226, 230);
   border-radius: 5px;
@@ -552,4 +552,3 @@ body.td-documentation {
   }
 }
 
-