apply new cs fixes (#14)

Author: dbu

tests/PromiseTest.php

@@ -4,7 +4,6 @@
 
 namespace Http\Adapter\Guzzle7\Tests;
 
-use Exception;
 use GuzzleHttp\Promise\RejectedPromise;
 use Http\Adapter\Guzzle7\Promise;
 use PHPUnit\Framework\TestCase;
@@ -20,10 +19,10 @@ class PromiseTest extends TestCase
 
     public function testNonDomainExceptionIsHandled(): void
     {
-        $this->expectException(Exception::class);
+        $this->expectException(\Exception::class);
 
         $request = $this->prophesize(RequestInterface::class);
-        $promise = new RejectedPromise(new Exception());
+        $promise = new RejectedPromise(new \Exception());
 
         $guzzlePromise = new Promise($promise, $request->reveal());