[Backport 2.x] Added new Setting property UnmodifiableOnRestore to prevent updating settings on restore snapshot#17116

sohami merged 2 commits intoopensearch-project:2.xopensearch-project/OpenSearch:2.xfrom

anntians:backport/backport-16957-to-2.xanntians/OpenSearch:backport/backport-16957-to-2.xCopy head branch name to clipboard