Create a Python script to monitor parsing

[erictleung]

I'm imaginging a Python script that is run at the end of the GitHub Actions to simply output how the parsing is doing.

E.g., parse the JSON file and note basic distributions for number of links per date, distribution of links with dates, duplicate GUIDs in the RSS file, etc.

This issue can stay open for discussion on other metrics to keep track of to get some feedback on how the parsing is doing.