Migrate validator client to clap derive #19766

Job	Run time
check-code	23s
check-msrv	5m 30s
Check for 'skip-ci' label	1s
lockbud	14m 31s
target-branch-check	1s
op-pool-tests	24m 2s
beacon-chain-tests	37m 5s
release-tests-ubuntu	26m 57s
debug-tests-ubuntu	7m 55s
ef-tests-ubuntu	10m 57s
network-tests	27m 24s
slasher-tests	3m 51s
state-transition-vectors-ubuntu	8m 14s
basic-simulator-ubuntu	22m 3s
cargo-sort	14s
cargo-udeps	7m 37s
cli-check	14m 49s
compile-with-beta-compiler	15m 16s
execution-engine-integration-ubuntu	13m 14s
fallback-simulator-ubuntu	19m 42s
release-tests-windows	38m 37s
test-suite-success	0s
	4h 58m 23s

Provide feedback