Error: Parsing error: 'import' and 'export' may appear only with 'sourceType: module'

[hoanmq]

I cloned the latest version from the master, followed the instructions, and everything was fine when I ran 'yarn dev'. But when I ran 'yarn build', I encountered the error 'Error: Parsing error: 'import' and 'export' may appear only with 'sourceType: module''. I'm not sure if I missed a configuration or if I did something wrong at some step. Please help, thanks