Remove backup article redirection entries

Removed multiple redirection entries for backup articles.

Author: Saisang

.openpublishing.redirection.json

@@ -1,20 +1,5 @@
 {
   "redirections": [
-    {
-      "source_path": "articles/backup/backup-azure-enhanced-soft-delete-tutorial.md",
-      "redirect_url": "/azure/backup/secure-by-default",
-      "redirect_document_id": false
-    },
-    {
-      "source_path": "articles/backup/backup-azure-security-feature-cloud.md",
-      "redirect_url": "/azure/backup/secure-by-default",
-      "redirect_document_id": false
-    },
-    {
-      "source_path": "articles/backup/quick-backup-azure-enable-enhanced-soft-delete.md",
-      "redirect_url": "/azure/backup/secure-by-default",
-      "redirect_document_id": false
-    },
     {
       "source_path": "articles/azure-functions/functions-proxies.md",
       "redirect_url": "/previous-versions/azure/azure-functions/functions-proxies",