fix sf/yaml dep version (4.0 introduces BC)

Author: klatys

composer.json

@@ -9,7 +9,7 @@
     "ext-curl": "*",
     "skrz/meta": "^3.1",
     "symfony/finder": "~2.7|~3.0|~4.0",
-    "symfony/yaml": "~2.7|~3.0|~4.0"
+    "symfony/yaml": "~4.0"
   },
   "require-dev": {
     "cdn77/coding-standard": "^0.5",

src/Response/ResponseData.php

@@ -97,6 +97,9 @@ public function getYaml() : ?string
      */
     public function getParsedYaml(int $flags = 0) : array
     {
-        return Yaml::parse($this->getYaml(), $flags);
+        return Yaml::parse(
+            (string) $this->getYaml(),
+            $flags
+        );
     }
 }