token 2022: add alloc_and_serialize for fixed-len extensions #3872

Job	Run time
cargo-build-test-cli	6h 0m 15s
cargo-build-test-cli	26m 47s
cargo-test-sbf	25m 59s
cargo-test-sbf	25m 59s
cargo-test-sbf-associated-token-account	9m 7s
cargo-test-sbf-associated-token-account	9m 7s
cargo-test-sbf-transfer-hook	8m 32s
cargo-test-sbf-transfer-hook	8m 32s
cargo-test-sbf-twoxtx	15m 24s
cargo-test-sbf-twoxtx	15m 24s
cargo-test-token-2022-serde	2m 57s
cargo-test-token-2022-serde	2m 57s
cargo-build-test-transfer-hook-cli	19m 49s
cargo-build-test-transfer-hook-cli	19m 49s
js-test	5m 1s
js-test	5m 1s
	9h 20m 40s

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