refactor: 💡 convert form error components to nested structure

addons/rose/addon/components/rose/form/errors.js

@@ -1,10 +0,0 @@
-import Component from '@ember/component';
-import layout from '../../../templates/components/rose/form/errors';
-
-/**
- * A container for error messages.  Yields the error message component.
- */
-export default Component.extend({
-  layout,
-  tagName: '',
-});

addons/rose/addon/components/rose/form/errors/message.js

@@ -1,10 +0,0 @@
-import Component from '@ember/component';
-import layout from '../../../../templates/components/rose/form/errors/message';
-
-/**
- * A simple, styled error message.  Do not use directly.
- */
-export default Component.extend({
-  layout,
-  tagName: '',
-});