refactor(expect): remove timeouts in run configs using `hold_uart.exp`

This change removes all timeouts applied to the `hold_uart.exp` script
in run configurations, as the timeout is not used by this script.

Signed-off-by: Chris Kay <chris.kay@arm.com>
Change-Id: I1f4fb72f1bee981a4f79b504097b8a0a01226328
1 file changed