message: Use url encoded strings for list keys prefixes
diff: @@ -24,7 +24,7 @@ pub fn list(
  let params = ListNamespaceKeysParams {
  limit: None, // Defaults to 1000 (the maximum)
  cursor: None,
  - prefix: prefix.map(str::to_string),
  + prefix: prefix.map(kv::url_encode_key),
  };
  let mut request_params = ListNamespaceKeys {
  