Fix Client::getTime()

fixes #298

Author: TomA-R

src/Bigcommerce/Api/Client.php

@@ -474,7 +474,7 @@ public static function getCustomerLoginToken($id, $redirectUrl = '', $requestIp
     }
 
     /**
-     * Pings the time endpoint to test the connection to a store.
+     * Pings the time endpoint to test the connection to the BigCommerce API.
      *
      * @return ?DateTime
      */
@@ -486,7 +486,9 @@ public static function getTime()
             return null;
         }
 
-        return new DateTime("@{$response}");
+        $seconds = floor($response / 1000);
+        $microseconds = $response % 1000;
+        return DateTime::createFromFormat('U.u', sprintf('%d.%03d', $seconds, $microseconds));
     }
 
     /**

test/Unit/Api/ClientTest.php

@@ -210,9 +210,9 @@ public function testGetTimeReturnsTheExpectedTime()
         $this->connection->expects($this->once())
             ->method('get')
             ->with('https://api.bigcommerce.com/time', false)
-            ->will($this->returnValue($now->format('U')));
+            ->will($this->returnValue('1718283600000'));
 
-        $this->assertEquals($now->format('U'), Client::getTime()->format('U'));
+        $this->assertEquals('2024-06-13 13:00:00', Client::getTime()->format('Y-m-d H:i:s'));
     }
 
     public function testGetStoreReturnsTheResultBodyDirectly()