We had disabled UBSANs detection of passing null to parameters tagged as non-null for WT-2631:
https://github.com/mongodb/mongo/blob/8eea87b6b90499d526e085ba723ddf989b837994/SConstruct#L2326-L2333
With WT-2631 resolved, we should be able to remove this override.
WT-2631 nullptr is passed for parameters marked with attribute non-null