This document is a relatively minor publication from a dicastery. These days, you can generally expect Latin editions will be produced for major documents such as papal encyclicals, and may only become available when the document is prepared, after its initial publication, for inclusion in the Acta Apostolicae Sedis.
Machine learning is a "noun phrase" and not a verb, so it does not conjugate, the words in the phrase decline. I personally would go with "ēruditio machinārum" (the learning of the machines).
The word ēruditio (learning/erudition) is in the nominative case while machinārum is in the genitive plural of māchina.
Note: I am a noob Latin language learner, if you're interested check out the great textbook LLPSI[0]!
