See if there's a better way to track alignment of `pactaDataUrl` across config

[jdhoffa]

          NB (probably make a new issue): I wonder if we can define this centrally in one place? Seems like it would be very easy for this to get out of sync (across all configs and all `workflow.pacta.*` repos).

Originally posted by @jdhoffa in #47 (comment)

This seems like something that appears many times, across many different files in the workflow.pacta.* world, and it falling out of sync could cause difficult to understand bugs.