get_commenters doesn't find commenters when dependabot makes a PR before the script completes.

[housten]

In 3 of the last 4 classes I led, script step 2 could not import the commenters because dependabot created issues before step 1 of the script completed and get_commenters is hardcoded to check issue 1.

This one was yesterday:
dependabot: SolidifyDemo/GHDev07#1
add collaborator issue: SolidifyDemo/GHDev07#3

I have created a fix, that I tested on https://github.com/SolidifyDemo/GHDev07, so the _slides folder now contains files for all the commenters on issue 3. I will submit a PR for it.