Enable side tag feature

CentOS Infra issue/request

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As a automotive kernel developer, I have some packages that depend on each other that I wish to build: qcom-scmi depends on downstream-dtbs

The recommended way for multi-package update is using side tags

When trying this feature, I see:

$ cbs add-sidetag automotive10s-packages-main-el10s-build
2026-02-23 13:30:52,705 [ERROR] koji: GenericError: Invalid method: createSideTag

Looking at createSideTag, it's indeed not listed as part of the API:

$ cbs list-api | grep createSideTag
<empty>

Is it possible to enable it? Alternatively, any other recommended approach to build multiple, dependent packages in CBS?

(Locally, I solve this using mock install and mock --no-clean)