Change trigger for Obsolete term template to a label vs. open, reopened

[twhetzel]

For testing the GH Action, the initial action that triggered the action was by opening or re-opening an issue,

on:
  issues:
    types: [opened, reopened]

This action trigger should be changed to adding a label and the label value should be 'on the list'.

See https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#issues

[twhetzel]

And change to run on issues where the Issue TITLE vs. Body contains the word obsolete.

[twhetzel]

Re-order steps so that other steps don't run if the label is not on the list

[twhetzel]

done