Need better update/overview handling

[hcayless]

The current system will only reflect user changes if they have enabled actions in their own GitHub repo. Otherwise the spec_lists.json file hosted at https://github.com/TEIC/TEI/blob/dev/P5/spec_lists.json will not get rebuilt when they push changes.

Consider replacing is with a process that runs on the tei-c.org server and generates the overview data for each user. This would not take up a huge amount of room, could be periodically cleaned up, and would mean we could dispense with the GitHub Action that builds the spec list.