Implement the segment caching feature of Sequencer API

[seeflood]

What would you like to be added:
Implement the segment caching feature of Sequencer API
You can refer to Leaf to do double buffer optimization
The function to be implemented is at https://github.com/mosn/layotto/blob/main/pkg/runtime/sequencer/cache.go

The design doc(in chinese) is at https://mosn.io/layotto/#/zh/design/sequencer/design

Why is this needed:

[seeflood]

This task will be assigned to @ZLBer

[ZLBer]

建议给sequencer增加是否支持segment的方法，现在GetSegment方法功能不够单一, 在写catch的时候发现有时候只想查看sequencer是否支持segment,并不想直接申请一段。

[seeflood]

@ZLBer 本来考虑过加个isSupportCache() 后来改成GetSegment了
GetSegment也能解决你说的问题呀，只想判断是否支持segment、不想取号的话，size传0，GetSegment(0)

[ZLBer]

这样啊 怪怪的

[seeflood]

这样啊 怪怪的

是有点
其实我原来第一版就写的一个单独的判断函数（叫supportSegement还是啥来着忘了）
后来和其他人讨论，别人觉得没必要单独加一个函数；然后我看了下Dapr state组件的BulkGet 设计风格也是往返回结果里加个support，就改成这样了。当时觉得这种其实是个人喜好问题，没啥对与错，既然Dapr之前是这风格那就保持一致吧，就改了
或者你也可以把你的想法写下，我们下周讨论下

[seeflood]

现在实现的话可以先写GetSegment(0) 后面真要改成supportSegment也简单

[ZLBer]

fine

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[github-actions]

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