Fix heading level in 5.1 release notes

docs/releases/5.1.md

@@ -536,7 +536,7 @@ Additionally, two new events will be dispatched when the dialog visibility chang
 | Show   | `w-dialog:shown`  |
 | Hide   | `w-dialog:hidden` |
 
-## Shared template `.../tables/attrs.html` has been renamed to `.../shared/attrs.html`
+### Shared template `.../tables/attrs.html` has been renamed to `.../shared/attrs.html`
 
 The undocumented shared template for rendering a dict of `attrs` to HTML, similar to Django form widgets, has been renamed.