What could be the problem when updating Angular 14 to version 15 causes "ng serve" to fail due to "Module parse failed: Unexpected TOKEN"?

Question

I'm trying to update the Angular v14 to v15. We are using the hybrid application, with just a few AngularJS components left to rewrite. With v14 we got the same error, but we managed to fix it by putting paths of those .scss files in the angular.json file under "styles". With Angular 15 this issue reappeared and this doesn't seem to fix it. To note we are also using Angular Builders - Custom Webpack, with the following settings:

module.exports = {
    module: {
        rules: [
            {
                test: /\.js$/,
                exclude: /node_modules/,
                use: {
                    loader: 'babel-loader'
                }
            },
            { test: /\.html$/, use: { loader: 'raw-loader' } },
        ],
    }
};