Update InstantStyle usage in IP-Adapter documentation (#7806)
* enable control ip-adapter per-transformer block on-the-fly
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Co-authored-by: sayakpaul <spsayakpaul@gmail.com>
Co-authored-by: ResearcherXman <xhs.research@gmail.com>
Co-authored-by: YiYi Xu <yixu310@gmail.com>
