use Yaml class classloader

Author: takashima0411

util/src/main/java/io/kubernetes/client/util/Yaml.java

@@ -100,7 +100,7 @@ private static void initModelMap() throws IOException {
     initApiGroupMap();
     initApiVersionList();
 
-    ClassPath cp = ClassPath.from(ClassLoader.getSystemClassLoader());
+    ClassPath cp = ClassPath.from(Yaml.class.getClassLoader());
     Set<ClassPath.ClassInfo> allClasses = cp.getTopLevelClasses("io.kubernetes.client.models");
 
     for (ClassPath.ClassInfo clazz : allClasses) {