Fix wrong exception message.

Author: mathieutu

src/Drivers/YamlDriver.php

@@ -16,7 +16,7 @@ public function serialize($data): string
         }
 
         if (! is_array($data)) {
-            throw new CantBeSerialized('Only strings can be serialized to json');
+            throw new CantBeSerialized('Only array and strings can be serialized to yaml.');
         }
 
         return Yaml::dump($data, PHP_INT_MAX);