Correct code styling

Author: jasonmccreary

README.md

@@ -29,29 +29,25 @@ abstract class TestCase extends BaseTestCase
 ## Assertions
 This package adds several assertions helpful when writing [Http Tests](https://laravel.com/docs/5.8/http-tests).
 
-```
-php
+```php
 assertActionUsesFormRequest(string $controller, string $method, string $form_request)
 ```
 
 Verifies the _action_ for a given controller performs validation using the given form request.
 
 
 ## Matchers
-```
-php
+```php
 LaravelMatchers::isModel(Model $model = null)
 ```
 Matches an argument _is_ the same as `$model`. When called without `$model`, will match any argument of type `Illuminate\Database\Eloquent\Model`.
 
-```
-php
+```php
 LaravelMatchers::isCollection(Collection $collection = null)
 ```
 Matches an argument _equals_ `$collection`. When called without `$collection`, will match any argument of type `Illuminate\Support\Collection`.
 
-```
-php
+```php
 LaravelMatchers::isEloquentCollection(Collection $collection = null)
 ```
 Matches an argument _equals_ `$collection`. When called without `$collection`, will match any argument of type `\Illuminate\Database\Eloquent\Collection`.