Add info for People Group on how to best self serve in Workday

Why is this change being made?

With many new reports and resources added to Workday this year, and new PBPs joining the team, I thought it would be helpful to have a centralized place to go for PBPs and potentially other People Group folks who use this data and may need a reminder of where to access what. I made this Workday centric, but it might be useful to have a similar "key" for Tableau dashboards as the team develops them.

Author Checklist

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