message: Fix typing of readFile function
diff: @@ -10,7 +10,7 @@ import promisify from 'util.promisify';
  import type { Stats } from 'fs';
  -type ReadFileFn = (filename: string, enc?: string) => Promise<string>;
  +type ReadFileFn = (filename: string, enc?: string) => Promise<Buffer | string>;
  type WriteFileFn = (
  filename: string,
  data: Buffer | string,
  