Scheduling error run first xxday in a month

[neodata83]

Describe the bug

I would like to set the Scheduling to run every first Sunday of the month at 10pm. the cron looks like this 0 0 10 * * SUN#1 but wehn i start the container i get this error:

time="2023-04-09T09:11:47+02:00" level=error msg="Failed to parse int from SUN#1: strconv.Atoi: parsing \"SUN#1\": invalid syntax"

same wehn i try with 0 0 10 * * 7#1

Steps to reproduce

1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

Expected behavior

Watchtower should run every first Sunday in a month at 10am

Screenshots

No response

Environment

docker version 5:23.0.1-1debian.11bullseye

Your logs

time="2023-04-09T09:39:04+02:00" level=warning msg="Using an HTTP url for Gotify is insecure"
time="2023-04-09T09:39:04+02:00" level=debug msg="Sleeping for a second to ensure the docker api client has been properly initialized."
time="2023-04-09T09:39:05+02:00" level=debug msg="Making sure everything is sane before starting"
time="2023-04-09T09:39:05+02:00" level=debug msg="Retrieving running and restarting containers"
time="2023-04-09T09:39:05+02:00" level=debug msg="There are no additional watchtower containers"
time="2023-04-09T09:39:05+02:00" level=debug msg="Watchtower HTTP API skipped."
time="2023-04-09T09:39:05+02:00" level=error msg="Failed to parse int from 7#1: strconv.Atoi: parsing \"7#1\": invalid syntax"

Additional context

No response

[github-actions]

Hi there! 👋🏼 As you're new to this repo, we'd like to suggest that you read our code of conduct as well as our contribution guidelines. Thanks a bunch for opening your first issue! 🙏

[piksel]

I don't see anything about # in the docs, but I think it would be 0 0 10 1-7 * SUN.