feat: `std::hint::black_box` function. #16397

Job	Run time
build-acvm-js	1m 36s
build-nargo	2m 29s
build-noirc-abi	1m 7s
build-noir-wasm	3m 30s
Load critical library list	4s
yarn-lock	1m 4s
noirc_abi	1m 39s
ACVM JS (Node.js)	39s
ACVM JS (Browser)	1m 37s
noir_codegen	1m 2s
Noir JS	1m 2s
Example scripts	11s
Check external repo - ${{ matrix.project.repo }}	0s
noir_wasm	1m 56s
Integration Tests (Browser)	2m 15s
Integration Tests (Node)	2m 17s
End	1s
	22m 29s

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