docs: format with prettier (#1218)

docs/getting-started/Plugin development.md

@@ -2,10 +2,10 @@
 
 Backstage plugins provide features to a Backstage App.
 
-Each plugin is treated as a self-contained web app and can include almost any type of content.
-Plugins all use a common set of platform APIs and reusable UI components.
-Plugins can fetch data from external sources using the regular browser APIs or by depending on
-external modules to do the work.
+Each plugin is treated as a self-contained web app and can include almost any
+type of content. Plugins all use a common set of platform APIs and reusable UI
+components. Plugins can fetch data from external sources using the regular
+browser APIs or by depending on external modules to do the work.
 
 <!-- MOVED TO create-a-plugin.md ## Creating a new plugin
 On your command line, invoke the `backstage-cli` to create a new plugin:
@@ -27,17 +27,19 @@ plugin directly by navigating to `http://localhost:3000/my-plugin`.*
 
 - Consider writing plugins in `TypeScript`.
 - Plan the directory structure of your plugin so that it becomes easy to manage.
-- Prefer using the Backstage components, otherwise go with [Material-UI](https://material-ui.com/).
+- Prefer using the Backstage components, otherwise go with
+  [Material-UI](https://material-ui.com/).
 - Check out the shared Backstage APIs before building a new one.
 
 ## Plugin concepts / API
 
 ### Routing
 
-Each plugin is responsible for registering its components to corresponding routes in the app.
+Each plugin is responsible for registering its components to corresponding
+routes in the app.
 
-The app will call the `createPlugin` method on each plugin, passing in a `router` object with a set
-of methods on it.
+The app will call the `createPlugin` method on each plugin, passing in a
+`router` object with a set of methods on it.
 
 ```jsx
 import { createPlugin, createRouteRef } from '@backstage/core';