Implement PHP CS Fixer and a coding standard to follow (#471)

* Create PHP CS Fixer config and add to CI workflow

* Run php cs fixer on project

* Add newline at end of file

* Update to use PHP CS Fixer v3

* Run v3 config on project

* Run seperate config in CI

app/Http/Controllers/V1/Invoice/InvoiceTemplatesController.php

@@ -19,7 +19,7 @@ class InvoiceTemplatesController extends Controller
         $invoiceTemplates = InvoiceTemplate::all();
 
         return response()->json([
-            'invoiceTemplates' => $invoiceTemplates
+            'invoiceTemplates' => $invoiceTemplates,
         ]);
     }
 }