avoid 500s on slugify

packages/lib/slugify.ts

@@ -2,6 +2,9 @@
 // For eg:- "test-slug" is the slug user wants to set but while typing "test-" would get replace to "test" becauser of replace(/-+$/, "")
 
 export const slugify = (str: string, forDisplayingInput?: boolean) => {
+  if (!str) {
+    return "";
+  }
   const s = str
     .toLowerCase() // Convert to lowercase
     .trim() // Remove whitespace from both sides