chore: update slug

Author: jivanova

upgrade/breaking-changes/3-0-0.md

@@ -2,7 +2,7 @@
 title: 3.0.0
 description: Handle the changes in the 3.0.0 release of the Telerik UI for Blazor components.
 page_title: Breaking Changes in 3.0.0
-slug: changes-in-3.0.0
+slug: changes-in-3-0-0
 position: 1
 ---