schedule-builder does not move already EOL 1.33 to eol.yaml

[azlkiniue]

What happened:

The schedule-builder skipped moving 1.33 to eol.yaml because in schedule.yaml it doesn't contain next release information.

What you expected to happen:

schedule-builder should be able to move kubernetes releases to eol without relying on the next release information.

How to reproduce it (as minimally and precisely as possible):

Run this command in the k/website main branch
schedule-builder -uc data/releases/schedule.yaml -e data/releases/eol.yaml
or just see the CI pipeline here: Update schedule.yaml

This message should be appear:
level=warning msg="Next release not set for 1.33, skipping"

Anything else we need to know?:

This problem discovered after I'm trying to create PR kubernetes/website#56364 for k/website. A contributor said that I should use schedule-builder but after I tried it manually the tool was not worked as intended. I investigated further and found that it was caused from an earlier PR kubernetes/website#56216.

Environment:

Installed latest schedule-builder with:
go install k8s.io/release/cmd/schedule-builder@latest

[azlkiniue]

/assign