Create manual publishing build trigger

[hepabolu]

it's nice to be able to trigger the publishing workflow manually. If all configurations are set just right in the exact the right order, the build will be triggered when the tag is added. When something is not right, the only way to trigger another release is to bump the version and create a new matching tag.
So we need a manual trigger, but that means the workflow steps and ci scripts need to be changed to allow for this extra trigger.

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

idea about how to get the latest tag:
https://gist.github.com/lukechilds/a83e1d7127b78fef38c2914c4ececc3c