Calling project.config() with an environment breaks addon supplied config

I'm not sure exactly what's going on here, but I've managed to boil it down to a [minimal reproduction repo](https://github.com/davewasmer/ember-addon-config-bug).

If an addon calls `this.project.config('development')` in it's `setupPreprocessorRegistry()` hook, it appears to break at least some (maybe all) addon-supplied config.

## Reproduction steps

1. Clone down the repo
2. Run `ember server`
3. Inspect the contents of the config meta tag. Note the presence of the `_APPLICATION_TEMPLATE_WRAPPER` key in the encoded config object. This is the expected, correct behavior.
4. Open `lib/bug-exposer/index.js`
5. Add an environment parameter to the `this.project.config` invocation (i.e. `this.project.config('development')`.
6. Restart the server
7. Inspect the contents of the config meta tag. Note the **absence** of the `_APPLICATION_TEMPLATE_WRAPPER` key in the encoded config object.

It appears that the act of calling `this.project.config()` _with an environment parameter_ has caused the `@ember/optional-features` addon config to break.

## Errata

I haven't figured out exactly what's going on here, but I figured I'd brain dump the boundaries of what I have discovered so far.

* I'm not sure if some or all addon-supplied config breaks. The test repo demonstrates the issue with `@ember/optional-features`. It's also impacting a private addon we are using in combination with [ember-template-component-import](https://github.com/crashco/ember-template-component-import) which calls `project.config` in the `setupPreprocessorRegistry` hook.

* It can break from a deeply nested addon. I.e. an app will break if it depends on addon A, which depends on addon B, which makes the offending call.