Remove inactive sources from indicator status dashboard

[rzats]

Prerequisites:

• [X] Unless it is a hotfix it should be merged against the dev branch
• [X] Branch is up-to-date with the branch to be merged with, i.e. dev
• [x] Build is successful
• [X] Code is cleaned up and formatted

Summary

Prevents the inactive/stale sensors from showing up in the indicator status dashboard. Before:

After:

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[rzats]

@melange396 that information is already used here, where we filter out a bunch of sensors where the active property in the metadata is set to false. However, for the inactive sensors currently on the dashboard, that property is true.

A "smarter" solution could be to dynamically filter out all sensors that are N days out of date, which is similar to the thought process used to create the hardcoded list in the first place. I'd suggest a 180-day threshold in that case.

[melange396]

We got rid of the inactive sources by updating the signal metadata in https://github.com/cmu-delphi/delphi-epidata/pull/1259#issuecomment-1758071698 and https://github.com/cmu-delphi/delphi-epidata/pull/1306#issuecomment-1758124724.

The change in this PR would hide signals marked active that havent been updated for ~half a year, which is good for keeping the dashboard clean but it might obscure signals that we need to take action on (like marking them inactive or by fixing them in some other way). I'm going to close this for now, but we can revisit it later if something similar comes up.