Update pd-scheduling-best-practices.md (#3437)
Update pd-scheduling-best-practices.md (#3437)

* Update pd-scheduling-best-practices.md

* Update pd-scheduling-best-practices.md

* refine format

* Apply suggestions from code review

Co-authored-by: TomShawn <3d0966147538bc5ab020e8dffa2c0b746f9728a6@users.noreply.github.com>
Co-authored-by: ti-srebot <354121b1fcd840b60f1eb3b56f3ea5cc78ec06dd@users.noreply.github.com>
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