Fix Pipeline: Add Ligaai into "#integration_classes"

What does this MR do and why?

Failed job https://jihulab.com/gitlab-cn/gitlab/-/jobs/12738958

之前添加到 IntegrationsHelpers#integrations 方法里的 ligaai 没有添加到 IntegrationsHelpers#integration_classes 方法里，导致 Spec 报错。

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