Proto/DAL: Use the attestation lag of denounced level and not of migration level
What
Use the attestation lag of the denounced level.
Why
Because to know what the baker attested, we have to use the parameters of the time they attested.
How
By simply calling the function on the expected level.
Manually testing the MR
I would expect the test introduced by !19547 (merged) to fail on !19442 (merged) without this fix.