Add "break" support to "pio test" ?

For STM32 via ST-Link, the RTS and DTR modes to reset an uploaded test app don't work. The documented workaround is to add a 2s startup delay.

To considerably speed things up when running multiple tests, pio test could send a BREAK on the serial port, which does an immediate reset.

Would it be possible to add an option to send a break once connected to the USB serial port?