when I use tsm register to transpile module which contains dynamic import, it's broken

• src/index.ts

async function main(){
  const mod = await import('./lib');
}
main();

• src/lib.ts

export const answer = 42;

It's broken

It's because esbuild will keep dynamic import for high version of node, even you set format=cjs evanw/esbuild#1636

when I set target to node12, it works fine now, because it will transform dynamic import to require

• tsm.js

module.exports = {
  common: {
   target: 'node12'
  }
}

so I think we could set target=node12 by default to support dynamic import by default