fix(rdkit): replace Descriptors.LabuteASA with rdMolDescriptors

[jiaodu1307]

fix(rdkit): replace Descriptors.LabuteASA with rdMolDescriptors.CalcabuteASA

[TKassis]

Thanks for the PR — checked this against RDKit 2026.03.3, and Descriptors.LabuteASA is not actually broken:

Descriptors.LabuteASA(m)            OK   -> 74.75705264447721
rdMolDescriptors.CalcLabuteASA(m)   OK   -> 74.75705264447721

Both resolve to the same implementation and return identical values — Descriptors.LabuteASA is a re-export of the rdMolDescriptors function. The current code runs correctly, so this change would be a no-op rather than a fix.

Closing on that basis. If you hit an actual error, please reopen with the traceback and the RDKit version — happy to take another look.

Separately: the genuine bug in this same file was Descriptors.FractionCsp3, which does raise AttributeError. That one is fixed in #213.