[iOS] Fix view removal process for AutofillContextAction.cancel

[koji-1009]

The removeFromSuperview in the hideTextInput method was triggering the save password, so I changed it to cleanUpViewHierarchy.

fix flutter/flutter#145681

sample app code

https://github.com/koji-1009/autofill_cancel_issue

before

before.mp4

after

after.mp4

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