fix flaky test deserializeArrayModel

Author: xinying7

modules/swagger-core/src/test/java/io/swagger/v3/core/serialization/ModelSerializerTest.java

@@ -121,10 +121,13 @@ public void serializeArrayModel() throws IOException {
 
     @Test(description = "it should deserialize an array model")
     public void deserializeArrayModel() throws IOException {
-        final String json = "{\"type\":\"array\",\"items\":{\"$ref\":\"#/definitions/Pet\"}}";
-        final Schema p = m.readValue(json, Schema.class);
+        final String json1 = "{\"type\":\"array\",\"items\":{\"$ref\":\"#/definitions/Pet\"}}";
+        final Schema p = m.readValue(json1, Schema.class);
+        String json2 = m.writeValueAsString(p);
+        JSONObject jsonObj1 = new JSONObject(json1);
+        JSONObject jsonObj2 = new JSONObject(json2);
         assertTrue(p instanceof ArraySchema);
-        assertEquals(m.writeValueAsString(p), json);
+        JSONAssert.assertEquals(jsonObj1, jsonObj2, true);
     }
 
     @Test(description = "it should not create an xml object for $ref")