[DOCS] Minor edit.
Original commit: elastic/x-pack-elasticsearch@9204612999f1f2c7cab65cb28339b6a04cbf6b87
@@ -29,7 +29,7 @@ realm will not be operational until the upgrade API is run on the security index
*Resolution:*
-You must manually upgrade the `.security` index to the 6.x format. For
+You must upgrade the `.security` index to the 6.x format. For
instructions, see
{stack-ref}/upgrading-elastic-stack.html#upgrade-internal-indices[Upgrading
internal indices].
