Add a plan file and patches that reference https://github.com/WebKit/MotionMark/tree/release/MotionMark1.3.1.
<rdar://problem/132444966>
Pull request: https://github.com/WebKit/WebKit/pull/31196
Committed 281363@main (94801c1fbac0): <https://commits.webkit.org/281363@main> Reviewed commits have been landed. Closing PR #31196 and removing active labels.