message: Update readme.md to point to security policy
diff: @@ -44,6 +44,10 @@ maximum memory efficiency. It allows you to directly access serialized data with
  *To contribute to this project,* see [CONTRIBUTING][].
  +## Security
  +
  +Please see our [Security Policy](SECURITY.md) for reporting vulnerabilities.
  +
  ## Licensing
  *Flatbuffers* is licensed under the Apache License, Version 2.0. See [LICENSE][] for the full license text.
  