chore: set major version on download-lambda

Co-authored-by: rishta

Author: stuartp44

modules/download-lambda/versions.tf

@@ -8,7 +8,7 @@ terraform {
     }
     null = {
       source  = "hashicorp/null"
-      version = "~> 3.0"
+      version = "~> 3"
     }
   }
 }