omni-node: --dev sets manual seal and allows --chain to be set #7172

Job	Run time
preflight / preflight	43s
preflight / ci-versions	1m 4s
test-full-crypto-feature	2m 39s
cargo-check-benches (master)	21m 0s
cargo-check-all-crate-macos	11m 5s
cargo-check-benches (current)	23m 41s
test-frame-ui	46m 27s
cargo-check-each-crate (1)	19m 56s
cargo-check-each-crate (2)	23m 34s
test-node-metrics	11m 2s
cargo-check-each-crate (3)	9m 36s
cargo-check-each-crate (4)	21m 24s
cargo-check-each-crate (5)	28m 13s
cargo-check-each-crate (6)	15m 13s
cargo-check-each-crate (7)	49m 27s
test-frame-examples-compile-to-wasm	3m 2s
test-deterministic-wasm	6m 31s
check-tracing	2m 23s
check-metadata-hash	6m 27s
node-bench-regression-guard	11s
All test misc tests passed	1s
	5h 3m 39s

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