Members with active conditionals can mark themselves as active

I didn't actually confirm that this is the case but it definitely looks like it is.

This will probably only require another check in `member_management_make_user_active`. Basically just confirm that the user isn't in `SELECT uid FROM conditional WHERE status = "Pending"` or something like that.

先檢查 `member_management_make_user_active` 以及現有的 `conditional` 記錄查詢或資料模型。確認目前是否可以將具有 `Pending` conditional 的使用者標記為 active，接著驗證這類使用者會被拒絕，而沒有 pending conditional 的使用者仍保有預期行為。Issue 中未指定測試檔案。

由索引模型根據 Issue 內容生成。