Gather metrics on GH Issues

[damccorm]

Now that we're using GH Issues, we should start gathering metrics on them so that we can update the dashboard.

This is step 1 of #21735

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[asf-ci]

Can one of the admins verify this patch?

[damccorm]

R: @kileys - if there's a better reviewer with more affinity, let me know, I'm basing this off of history in the .test-infra directory

[kileys]

LGTM