implement strict types

src/Application.php

-<?php
+<?php declare(strict_types=1);
 
 namespace LidoNation\Adapayments;
 

src/Config.php

-<?php
+<?php declare(strict_types=1);
 
 namespace LidoNation\Adapayments;
 

src/helpers.php

-<?php
+<?php declare(strict_types=1);
 
 use LidoNation\Adapayments\App\Services\AdaUsdQuoteService;
 

src/index.php

-<?php
+<?php declare(strict_types=1);
 
 const BASE_PATH = __DIR__.'/../';
 require BASE_PATH.'vendor/autoload.php';