message: Add deprecation notice to $data
diff: @@ -107,6 +107,9 @@ export async function readSecret(
  return ctx.env[secret.env];
  }
  if ('data' in secret) {
  + console.warn(
  + `Configuration uses deprecated $data key, use $include instead.`,
  + );
  const url =
  'path' in secret ? `${secret.data}#${secret.path}` : secret.data;
  const [filePath, dataPath] = url.split(/#(.*)/);
  