Changes back indices.create:alias to a simple dictionary (#1313) (#1317)

Co-authored-by: Sylvain Wallez <[email protected]>

Author: github-actions[bot]

output/schema/schema.json

@@ -42,7 +42,7 @@ export interface Request extends RequestBase {
   }
   body: {
     /* Aliases for the index. */
-    aliases?: Dictionary<Name, Alias> | Dictionary<Name, Alias>[]
+    aliases?: Dictionary<Name, Alias>
     /**
      * Mapping for fields in the index. If specified, this mapping can include:
      * - Field names