Make wast parse results serializable #3589

Job	Run time
Fuzz	3m 6s
Build wasm-tools (x86_64-linux, ubuntu-latest)	2m 30s
doc	1m 37s
Build wasm-tools (x86_64-macos, macos-latest)	3m 32s
check	2m 4s
Build wasm-tools (aarch64-macos, macos-latest, aarch64-apple-darwin)	6m 8s
Rustfmt	10s
Build wasm-tools (x86_64-windows, windows-latest)	4m 9s
Test (stable)	5m 19s
verify-publish	2m 23s
Build wasm-tools (aarch64-linux, ubuntu-latest, aarch64-unknown-linux-gnu)	2m 50s
Test (beta)	5m 3s
Test (nightly)	5m 10s
Test (macos)	7m 26s
Test on WebAssembly	3m 42s
Test (windows)	9m 3s
Record the result of testing and building steps	1s
	1h 4m 13s

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