dropdownPopupAlign not available for TreeSelect

[andynullwong]

• I have searched the issues of this repository and believe that this is not a duplicate.

Reproduction link

https://codepen.io/anon/pen/qPmYja?editors=0110

Steps to reproduce

Same issue as #7760 but the solution is no longer valid

What is expected?

TreeSelectProps interface to have dropdownPopupAlign

What is actually happening?

Unable to override overflow behavior. The options list top is align with page top, but not the pointed parent container.

Environment	Info
antd	3.20.7
React	16.8.6
System	Ubuntu 18.04.4 LTS
Browser	Chrome 80.0.3987.132 (Official Build) (64-bit)

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Also tried dropdownStyle and tried styling the component's overflow css property by setting dropdownClassName without success

[ant-design-bot]

Hi @AndyWongDev. Current version (3.x) is off the maintenance period. We may not accept pull request or fix bug with it anymore. This topic will be auto closed.

你好 @AndyWongDev，当前版本（3.x）已经过了维护期。我们不会再接受对其的相关 PR 与 issue。当前 topic 会被自动关闭。