Keep scheduled workflow alive via scheduled trigger

[bart-vmware]

Now also runs weekly so we can automatically catch dependency issues, but we should know this:

"In a public repository, scheduled workflows are automatically disabled when no repository activity has occurred in 60 days."

We could work around that by running:

git commit --allow-empty -m "Empty commit to keep repository alive"
git push

on each scheduled run.

Sure, and that would be pretty straightforward, but I think I'd rather add a separate job to do it like every 59 days than push an extra commit every week

Originally posted by @TimHess in #106 (comment)

[bart-vmware]

A less invasive approach would be to open a pull request and close it immediately.