[Feature]: support dynamic import by default

[hardfist]

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

[lukeed]

What versions of Node and esbuild are you using? The support range for import() was fixed here: evanw/esbuild#1772

It's not wise to make node12 the target for all runtimes, because it's untrue for non-12.x runtimes.

[hardfist]

I'm using [email protected]