Is ionic serve command working in your end ? if yes then it will be app build error or platform not configured properly.
Please try to remove the platform ionic cordova platform remove android and add again ionic cordova platform remove android then build the app.
Also here is our package.json file for dependencies: https://slack-files.com/T06A5EFRU-FRNFZ0KCM-94dc16afd0 .
First, you need to backup your package.json and rename node_modules to any name. Then replace package.json to our pacake.json and run npm install. It will create a new node_module folder and then run ionic serve and build command.