chore(NA): update versions after v8.11.5 bump (elastic#174706)

This PR is a simple update of our versions file after the recent bumps.

versions.json

@@ -13,16 +13,10 @@
       "currentMajor": true,
       "previousMinor": true
     },
-    {
-      "version": "8.11.4",
-      "branch": "8.11",
-      "currentMajor": true,
-      "previousMinor": true
-    },
     {
       "version": "7.17.17",
       "branch": "7.17",
       "previousMajor": true
     }
   ]
-}
+}