deprecation-workflow.js is included in prod builds

The blueprint tries to exclude `./app/deprecation-workflow.js` from non-development builds with a macro. But it doesn't do anything to prevent the same module from being included in the `compatModules`.

This would address the issue:

```diff
// ember-cli-build.js
return compatBuild(app, buildOnce, {
+ staticAppPaths: ['deprecation-workflow.js'],
});
```

But I don't love having this special one-off here. Perhaps it would be better to establish `./app/lib` and put all of that into `staticAppPaths` and move deprecation-workflow.js into `./app/lib`.