Add spell check and update Lighthouse book #19310

Job	Run time
Check for 'skip-ci' label	1s
lockbud	13m 30s
target-branch-check	1s
check-code	9m 27s
check-msrv	5m 19s
beacon-chain-tests	32m 46s
release-tests-ubuntu	21m 46s
op-pool-tests	22m 46s
release-tests-windows	30m 27s
basic-simulator-ubuntu	21m 11s
debug-tests-ubuntu	7m 24s
ef-tests-ubuntu	11m 5s
fallback-simulator-ubuntu	19m 26s
network-tests	25m 14s
slasher-tests	3m 40s
state-transition-vectors-ubuntu	9m 25s
cargo-udeps	7m 26s
cli-check	14m 43s
compile-with-beta-compiler	14m 48s
execution-engine-integration-ubuntu	13m 6s
test-suite-success	5s
	4h 43m 36s

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