Update GraphConstants.php

Author: MIchaelMainer

src/Core/GraphConstants.php

@@ -11,7 +11,7 @@
 * @package   Microsoft.Graph
 * @copyright 2019 Microsoft Corporation
 * @license   https://opensource.org/licenses/MIT MIT License
-* @version   GIT: 1.11.0
+* @version   GIT: 1.12.0
 * @link      https://graph.microsoft.io/
 */
 
@@ -24,7 +24,7 @@ final class GraphConstants
     const REST_ENDPOINT = "https://graph.microsoft.com/";
 
     // Define HTTP request constants
-    const SDK_VERSION = "1.11.0";
+    const SDK_VERSION = "1.12.0";
 
     // Define error constants
     const MAX_PAGE_SIZE = 999;
@@ -44,4 +44,4 @@ final class GraphConstants
 
     // Define server error constants
     const UNABLE_TO_PARSE_RESPONSE = "The HTTP client sent back an invalid response";
-}
+}