omni-node: --dev sets manual seal and allows --chain to be set #6898

Job	Run time
preflight / preflight	39s
preflight / ci-versions	1m 14s
cargo-check-benches (master)	21m 0s
cargo-check-benches (current)	23m 58s
test-frame-ui	46m 31s
cargo-check-each-crate (1)	20m 17s
test-full-crypto-feature	2m 35s
cargo-check-each-crate (2)	23m 28s
test-node-metrics	10m 54s
cargo-check-each-crate (3)	9m 30s
cargo-check-all-crate-macos	11m 32s
cargo-check-each-crate (4)	21m 44s
cargo-check-each-crate (5)	28m 16s
cargo-check-each-crate (6)	15m 11s
cargo-check-each-crate (7)	31m 48s
test-frame-examples-compile-to-wasm	3m 2s
test-deterministic-wasm	6m 26s
check-tracing	2m 25s
check-metadata-hash	6m 10s
node-bench-regression-guard	13s
All test misc tests passed	1s
	4h 46m 54s

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