Force include babel numeric separator (#3422)

babel.config.js

@@ -10,6 +10,7 @@ module.exports = (api) => {
         include: [
           '@babel/plugin-proposal-nullish-coalescing-operator',
           '@babel/plugin-proposal-optional-chaining',
+          '@babel/plugin-proposal-numeric-separator',
         ],
         loose: true,
         targets,