style: remove trailing whitespace (#335)

README.md

@@ -34,7 +34,7 @@ import Fastify from 'fastify'
 import cors from '@fastify/cors'
 
 const fastify = Fastify()
-await fastify.register(cors, { 
+await fastify.register(cors, {
   // put your options here
 })
 
@@ -51,7 +51,7 @@ You can use it as is without passing any option or you can configure it as expla
   - `String` - set `origin` to a specific origin. For example if you set it to `"http://example.com"` only requests from "http://example.com" will be allowed. The special `*` value (default) allows any origin.
   - `RegExp` - set `origin` to a regular expression pattern that will be used to test the request origin. If it is a match, the request origin will be reflected. For example, the pattern `/example\.com$/` will reflect any request that is coming from an origin ending with "example.com".
   - `Array` - set `origin` to an array of valid origins. Each origin can be a `String` or a `RegExp`. For example `["http://example1.com", /\.example2\.com$/]` will accept any request from "http://example1.com" or from a subdomain of "example2.com".
-  - `Function` - set `origin` to a function implementing some custom logic. The function takes the request origin as the first parameter and a callback as a second (which expects the signature `err [Error | null], origin`), where `origin` is a non-function value of the origin option. *Async-await* and promises are supported as well. The Fastify instance is bound to function call and you may access via `this`. For example: 
+  - `Function` - set `origin` to a function implementing some custom logic. The function takes the request origin as the first parameter and a callback as a second (which expects the signature `err [Error | null], origin`), where `origin` is a non-function value of the origin option. *Async-await* and promises are supported as well. The Fastify instance is bound to function call and you may access via `this`. For example:
   ```js
   origin: (origin, cb) => {
     const hostname = new URL(origin).hostname
@@ -122,7 +122,7 @@ import Fastify from 'fastify'
 import cors from '@fastify/cors'
 
 const fastify = Fastify()
-await fastify.register(cors, { 
+await fastify.register(cors, {
   hook: 'preHandler',
 })