Let "seats block" only be applied to team plan

What does this MR do and why?

Issue: https://jihulab.com/gitlab-cn/gitlab/-/issues/4245

To fix: https://jihulab.com/gitlab-cn/gitlab/-/issues/4306#note_4937149

QA 在 Staging 发现了团队版的 Bug：非团队版群组也被限制了席位数。当前 MR 用来修复此问题。

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