transaction: tests: deserialize ELIP203 test vectors #640

Job	Run time
Docs - stable toolchain (recent)	32s
Check WASM	30s
Test - stable toolchain	2m 49s
Prepare	4s
Test - nightly toolchain	2m 53s
Test - MSRV	13m 14s
Lint - nightly toolchain (recent)	35s
Docs - nightly toolchain (recent)	39s
	21m 16s

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