[Backport 8.x] Fix snapshot.create response (#2933)

(cherry picked from commit 030df6b)

Co-authored-by: Quentin Pradet <[email protected]>

Author: github-actions[bot]

output/openapi/elasticsearch-openapi.json

@@ -24,5 +24,6 @@ export class SnapshotShardFailure {
   node_id?: Id
   reason: string
   shard_id: Id
+  index_uuid: Id
   status: string
 }