lychee-version.yml seems to create PRs with null versions.

This should not happen. Maybe add a check if version is null to prevent the creation of such PRs. Maybe there is another solution.

Note that there is a related workflow & script for the documentation repository: https://github.com/lycheeverse/lycheeverse.github.io/blob/master/bump-lychee.sh
(at first I confused it with that repo & workflow)