dynamic import is not working when the imported library has been listed in externals.

[songshuzhong]

Bug report

What is the current behavior?
dynamic import is not working when the imported library has been listed in externals.

If the current behavior is a bug, please provide the steps to reproduce.

1. import
   import(/*webpackChunkName: "js-export-excel", webpackPrefetch: true */ 'js-export-excel')
   .then(res => {
   const options = {
   name: props.title || 'sheetjs',
   datas: [{
   sheetData,
   sheetName: props.title || 'sheetjs',
   sheetHeader: sheetLabel
   }]
   };
   new res.default(options).saveExcel();
   }).catch(e => {
   proxy.$message.error(e.message);
   console.error(e);
   });
2. config
   module.exports = {
   externals: {
   'js-export-excel': 'js-export-excel'
   }
   }；
   3.result
   Promise.resolve(/*! import() /).then(webpack_require.t.bind(null, /! js-export-excel */ "js-export-excel", 7)).then(function (res) {
   var options = {
   name: props.title || 'sheetjs',
   datas: [{
   sheetData: sheetData,
   sheetName: props.title || 'sheetjs',
   sheetHeader: sheetLabel
   }]
   };
   new res.default(options).saveExcel();
   }).catch(function (e) {
   proxy.$message.error(e.message);
   console.error(e);
   });

What is the expected behavior?

Other relevant information:
webpack version: 4.44.2
Node.js version: 14.18.1
Operating System: mac
Additional tools:

[alexander-akait]

Please create reproducible test repo, thanks