Fix spacing

Author: kategengler

content/ember-cli/v5/v1-addon-content-for-types.md

@@ -4,6 +4,7 @@ since: 6.3.0
 until: 7.0.0
 ---
 `app-prefix`, `app-suffix`, `tests-prefix`, and `tests-suffix` are deprecated as types passed to `contentFor`. See [RFC 1029](https://rfcs.emberjs.com/id/1029-deprecate-app-prefix) for more information.
+
 #### app-prefix
 
 Returning content from an addon's `contentFor()` hook for `type="app-prefix"` is deprecated. Addons will no longer be allowed to inject arbitrary javascript here. If you need to provide code that apps will run before booting, document that app authors should import and call your code at the start of their own `app.js` file.