test(chain): Add test for inserting `Header` into `LocalChain` #275

Job	Run time
Check no_std	48s
Build & Test Examples (example_cli)	25s
Build and test (stable, true, --no-default-features --features miniscript/no-std)	1m 41s
Check WASM	2m 2s
Build & Test Examples (example_bitcoind_rpc_polling)	30s
Build and test (stable, true, --all-features)	4m 21s
Build and test (1.63.0, --no-default-features --features miniscript/no-std)	2m 46s
Build & Test Examples (example_electrum)	48s
Rust fmt	11s
prepare	3s
Build & Test Examples (example_esplora)	1m 6s
Build and test (1.63.0, --all-features)	5m 38s
Build & Test Examples (example_wallet_electrum)	59s
Build & Test Examples (example_wallet_esplora_async)	1m 16s
Build & Test Examples (example_wallet_esplora_blocking)	1m 11s
Build & Test Examples (example_wallet_rpc)	1m 35s
clippy_check	1m 29s
	26m 49s

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