Summary

modern-module reduces the runtime code for external modules with dynamic import.

// source
const react = import('react')

// before
// ---snip---
"357": (function (module) {
module.exports = __WEBPACK_EXTERNAL_MODULE_react_alias__;
}),
// ---snip---
const react = await Promise.resolve(/* import() */ ).then(__webpack_require__.bind(__webpack_require__, 357))

// after
const react = import('react')

What did this PR mainly do:

1. In finish_modules hook of modern-module, find all ImportDependency dependencies that point to external modules.
2. In the module graph, find the block to which the dependency belongs and remove this dep; find the connection associated with this dependency and revoke it.
3. Add a new dependency to complete the ID replacement for the external module.

Concern:

The connection is revoked, does it need to add a new connection between the original module and external module with the new dependency, is there a proper method to do that?

Checklist

• Tests updated (or not required).
• Documentation updated (or not required).