[dv/alert_handler] Fix esc_receiver_driver behavior
[dv/alert_handler] Fix esc_receiver_driver behavior

When esc_receiver driver receives a ping_response, while responding to
the ping response, a real escalation signal interrupted.
In this case, design will abort the ping response, and directly jumpped
to escalation response.
Current `esc_receiver_driver` did not do anything but keep toggling the
resp_p/n, this behaivor is fine but makes the sequence harder to manage.

This PR update the behavior: Now the driver will abort the random
resp_p/n drives, and response to the real escalation signal without any
sig_int_err.

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

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