[dv/alert_handler] fix daily regression cases
[dv/alert_handler] fix daily regression cases

Fix corner case when timeout value small than 2

Signed-off-by: Cindy Chen <399ad771a111eac8923348b1e2af093034e5d4f1@google.com>

lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan