Usage of IsComObject now throws a MissingMethodException where previously it would not.

To repro attach the following script to an object and enter playmode:

```
using System;
using UnityEngine;

public class DynamicTest : MonoBehaviour
{
public int test = 10;
// Start is called before the first frame update
void Start()
{
#if DISABLE_COM
Debug.Log("COM DISABLED!!!");
#endif
dynamic dyn = test;
Type t = dyn.GetType();
Debug.Log("Type:"+t.FullName);
}

// Update is called once per frame
void Update()
{

}
}
```

Introduced by the mono upgrade