Allow renew time relative to the expiration date

[AlexanderS]

You can now set a negative value for days, that will be subtracted from the expiration date of the generated certificate.

This will fix #3413.

[AlexanderS]

I do not think, the error of the pipeline is related to the pull request.

[saudiqbal]

Any update on this PR?

[saudiqbal]

??? Nothing?

[heiko3]

Unfortunately, there has been no response to the pull request yet. We've been using this change in production for a long time, and it works very well. Given the different expiration times for server certificates at different CAs, this is very helpful, and the expiration times will continue to change in the future, so this change is very important for automation.
It's a shame that the pull request hasn't been implemented yet.

[saudiqbal]

Looks like someone else needs to take over this project, acmesh-official is not doing anything for pull requests.

[lukastribus]

Ultimately #4944 ARI support is going to fulfill this need in most cases, I can see that the work has already began.

The change in this PR would still be useful nonetheless of course.

[saudiqbal]

Please approve the PR for relative expiry date.