Improve the logging output on GitHub actions.
Improve the logging output on GitHub actions.

 * Flush the logs more aggressively.
 * Output GitHub Actions fold markers.

Signed-off-by: Tim 'mithro' Ansell <b1c1d8736f20db3fb6c1c66bb1455ed43909f0d8@mith.ro>

litex-hub/pythondata-auto