Agroal should be updated to function in a JPMS environment.

This can be done in two stages. The first (easy) stage is to assign an automatic module name to each relevant component of Agroal (here are my recommendations, which were easy because this project has a very sensible layout):

• io.agroal:agroal-api -> io.agroal.api
• io.agroal:agroal-narayana -> io.agroal.narayana
• io.agroal:agroal-pool -> io.agroal.pool

The second stage would be to develop module-info.java files for each component, which requires that all dependencies of each component are in turn modularized to at least the first stage described above. Since this can be a complicated process involving third-party library upgrades, my recommendation would be to produce these descriptors as the corresponding dependencies become modularized. The io.agroal.api and io.agroal.pool modules should be able to be fully modularized with a descriptor right away, since AFAICT they have no external dependencies.