flow: Bump OpenROAD for CTS virtual clock latency fix

Update the OpenROAD submodule to the private secure-fix-cts-propagated-clock commit that preserves virtual clock latency during CTS.

This lets the SDC virtual IO clock latency changes affect post-CTS timing and downstream QoR in CI.

Only the OpenROAD submodule pointer is changed.

Signed-off-by: Jaehyun Kim <jhkim@precisioninno.com>

Author: jhkim-pii