buildkite-agent cli does not support getting the soft_fail attribute from a step

Created by: jhchabran

In the context of fixing the build uploads, I stumbled on this problem below. I have sent an email to Buildkite support and will report back here.

2021-11-09 08:38:52 FATAL  Failed to get step: POST https://agent.buildkite.com/v3/steps/7d43d9b3-785b-4d7a-87a5-77ed88010b34/export: 400 `soft_fail` is currently not supported. Please contact [email protected] if you'd like it added!