Fixed typo in search for wrong type (#28645)

docs/reference/query-dsl/terms-query.asciidoc

@@ -93,7 +93,7 @@ GET /tweets/_search
         "terms" : {
             "user" : {
                 "index" : "users",
-                "type" : "user",
+                "type" : "_doc",
                 "id" : "2",
                 "path" : "followers"
             }