Update memo.md: document wasm GC segfault fix #23

Job	Run time
test-linux	1m 3s
test-macos	36s
cross-compile (x86_64-macos-none)	3m 3s
cross-compile (aarch64-linux-gnu)	3m 6s
cross-compile (aarch64-macos-none)	3m 1s
cross-compile (x86_64-linux-gnu)	3m 8s
	13m 57s

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