remove `drain_filter_swapping` in favor of std's `Vec::extract_if`

[petrosagg]

The std method has finally stabilized and it additionally preserves ordering!

Motivation

Tips for reviewer

Checklist

• [ ] This PR has adequate test coverage / QA involvement has been duly considered. (trigger-ci for additional test/nightly runs)
• [ ] This PR has an associated up-to-date design doc, is a design doc (template), or is sufficiently small to not require a design.
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• [ ] If this PR includes major user-facing behavior changes, I have pinged the relevant PM to schedule a changelog post.