update composer

Author: coolcodemy

composer.json

@@ -21,7 +21,7 @@
     "require": {
         "php": ">=5.5.0",
         "league/flysystem": "~1.0",
-        "runcloudio/b2-sdk-php" : "^1.2",
+        "runcloudio/b2-sdk-php" : "^1.3",
         "mikey179/vfsStream" : "*"
     },
     "require-dev": {