Single command for beacon node and checkpoint sync. Remove separate command for `trustedNodeSync`

[jgresham]

Is your feature request related to a problem? Please describe. No just a UX improvement

Describe the solution you'd like No need to run trustedNodeSync as a separate process/command at the beginning. Just run one command like so: <start beacon node as normal> --trusted-node-url=<checkpoint-sync-url>

Describe alternatives you've considered Most other clients support this

Additional context This will help simplify logic for apps that run nodes for users