Tutorial Error: Failed to load external module @babel/register

I get the following error when running the tutorial in Windows 10 using WSL (Ubuntu on Windows). I have followed the instructions and I keep getting this error.

```
$ gulp critical
[13:11:04] Failed to load external module @babel/register
[13:11:04] Requiring external module babel-register
[13:11:09] Using gulpfile /mnt/d/workspace/myapp/gulpfile.babel.js
[13:11:09] Starting 'lint'...
[13:11:09] Starting 'styles'...
[13:11:10] Starting 'scripts'...
[13:11:10] Starting 'images'...
[13:11:10] Starting 'fonts'...
[13:11:10] Starting 'extras'...
(node:383) [DEP0022] DeprecationWarning: os.tmpDir() is deprecated. Use os.tmpdir() instead.
[13:11:10] Finished 'images' after 661 ms
[13:11:10] Finished 'fonts' after 152 ms
[13:11:11] Finished 'lint' after 1.79 s
[13:11:11] Finished 'styles' after 1.38 s
[13:11:11] Finished 'scripts' after 942 ms
[13:11:11] Starting 'html'...

events.js:183
throw er; // Unhandled 'error' event
^
Error
at new JS_Parse_Error (eval at (/mnt/d/workspace/myapp/node_modules/uglify-js/tools/node.js:28:1), :1534:18)
at js_error (eval at (/mnt/d/workspace/myapp/node_modules/uglify-js/tools/node.js:28:1), :1542:11)
at croak (eval at (/mnt/d/workspace/myapp/node_modules/uglify-js/tools/node.js:28:1), :2089:9)
at token_error (eval at (/mnt/d/workspace/myapp/node_modules/uglify-js/tools/node.js:28:1), :2097:9)
at unexpected (eval at (/mnt/d/workspace/myapp/node_modules/uglify-js/tools/node.js:28:1), :2103:9)
at expr_atom (eval at (/mnt/d/workspace/myapp/node_modules/uglify-js/tools/node.js:28:1), :2630:9)
at maybe_unary (eval at (/mnt/d/workspace/myapp/node_modules/uglify-js/tools/node.js:28:1), :2792:19)
at expr_ops (eval at (/mnt/d/workspace/myapp/node_modules/uglify-js/tools/node.js:28:1), :2827:24)
at maybe_conditional (eval at (/mnt/d/workspace/myapp/node_modules/uglify-js/tools/node.js:28:1), :2832:20)
at maybe_assign (eval at (/mnt/d/workspace/myapp/node_modules/uglify-js/tools/node.js:28:1), :2856:20)
at expression (eval at (/mnt/d/workspace/myapp/node_modules/uglify-js/tools/node.js:28:1), :2875:20)
at simple_statement (eval at (/mnt/d/workspace/myapp/node_modules/uglify-js/tools/node.js:28:1), :2314:55)
at eval (eval at (/mnt/d/workspace/myapp/node_modules/uglify-js/tools/node.js:28:1), :2178:20)
at eval (eval at (/mnt/d/workspace/myapp/node_modules/uglify-js/tools/node.js:28:1), :2136:24)
at eval (eval at (/mnt/d/workspace/myapp/node_modules/uglify-js/tools/node.js:28:1), :2904:23)
at Object.parse (eval at (/mnt/d/workspace/myapp/node_modules/uglify-js/tools/node.js:28:1), :2915:7)
at /mnt/d/workspace/myapp/node_modules/uglify-js/tools/node.js:71:33
at Array.forEach ()
at Object.exports.minify (/mnt/d/workspace/myapp/node_modules/uglify-js/tools/node.js:66:15)
at /mnt/d/workspace/myapp/node_modules/gulp-uglify/minifier.js:65:22
at trycatch (/mnt/d/workspace/myapp/node_modules/gulp-uglify/minifier.js:15:12)
at DestroyableTransform.minify [as _transform] (/mnt/d/workspace/myapp/node_modules/gulp-uglify/minifier.js:64:19)
```