ContainsSingle codefix False positive

## Describe the bug

False Positive when applying codefix for MSTEST0037

## Steps To Reproduce

```cs
Assert.AreEqual(1, collection.Count(x => x == 1));
```

## Expected behavior

```cs
Assert.ContainsSingle(x => x == 1, collection);
```

## Actual behavior

```cs
Assert.ContainsSingle(1, u => u == "System", resultUsings);
```