GitHub Actions: use calens action instead of docker-run-action

[DeepDiver1975]

use this instead: https://github.com/actionhippie/calens/tree/master

docker-run-action is generating semicolon_delimited_script which causes the git-commit-push action to fail
refs https://github.com/owncloud/ios-app/actions/runs/11013217572/job/30581072336