improvements following live insertion walkthrough

[geoknee]

• Why is this PR failing https://github.com/ethereum-optimism/superchain-registry/pull/402 ?
• We should run the contract versions check first, and if it fails we print a message and don't bother running the remaining tests which depend on the contract versions being correct

[sbvegan]

It looks like this was the issue: https://github.com/ethereum-optimism/superchain-registry/pull/409

We'll have them rebase their PR and the error should go away