enh: add open new submission to peer review status dashboard

[lwasser]

The current dashboard: https://www.pyopensci.org/metrics/peer-review/peer-review-status-dashboard.html has all of the pieces of data that an EiC would need to figure out what works needs to be done except for open "new submissions".

Let's add another section to this metrics page that summarizes new open submissions, ordered by date opened and number of days open. These will be issues that an eic hasn't yet reviewed

Below that let's add a "seeking editor" section to list reviews that need an editor.

This will help our newly formed EiC team move peer review forward.