Suggestion to rewrite as ??= is incorrect

(Visual Studio)

In the following code:

```
using UnityEngine;

public class Billboard : MonoBehaviour
{
public Camera Camera;

private void Start()
{
if (Camera is null)
{
Camera = Camera.main;
}
}

private void Update()
{
transform.LookAt(Camera.transform.forward);
}

private void OnDrawGizmos()
{
Debug.DrawRay(transform.position, transform.forward);
}
}
```

It suggests to rewrite as `Camera ??= Camera.main` which won't work.

But if you'd write this, the suggestion doesn't show which is correct:

```
if (Camera == null)
{
Camera = Camera.main;
}
```

No source files or tests are named. Reproduce the inspection in Visual Studio using both code snippets from the issue, then trace the analyzer or quick-fix responsible for suggesting ??=. Done means the inspection no longer proposes an invalid rewrite for the first snippet while preserving correct behavior for the second.

Written by the indexing model from the issue text.