`dotnet format` on Linux incorrectly reports CS0660 warning for generated partial class with IEquatable<> implementation

### To Reproduce

`dotnet format` on Linux reports no issues with the following code:

```
public partial class MyClass : IEquatable
{
public bool Equals(MyClass? other) => throw new NotImplementedException();

public override bool Equals(object? obj) => Equals(obj as MyClass);

public override int GetHashCode() => throw new NotImplementedException();

public static bool operator ==(MyClass? lhs, MyClass? rhs) => lhs is null ? rhs is null : lhs.Equals(rhs);

public static bool operator !=(MyClass? lhs, MyClass? rhs) => !(lhs == rhs);
}
```

However, running `dotnet format --verify-no-changes` results in a CS0660 warning if I use the [OneOf](https://github.com/mcintyre321/OneOf) library's source generator.

```
[GenerateOneOf]
public partial class MyClass : OneOfBase, IEquatable
{
public bool Equals(MyClass? other) => throw new NotImplementedException();

public override bool Equals(object? obj) => Equals(obj as MyClass);

public override int GetHashCode() => throw new NotImplementedException();

public static bool operator ==(MyClass? lhs, MyClass? rhs) => lhs is null ? rhs is null : lhs.Equals(rhs);

public static bool operator !=(MyClass? lhs, MyClass? rhs) => !(lhs == rhs);
}
```

`[GenerateOneOf]` causes an additional partial class definition for `MyClass` to be created. This seems to be confusing `dotnet format` and making it believe that `object.Equals` has not been overridden even though it has. I get:

`error CS0660: 'MyClass' defines operator == or operator != but does not override Object.Equals(object o)`

Running `dotnet-format` without `--verify-no-changes` causes it to insert a second `object.Equals` override which then causes the code to fail to compile.

Note that this issue does not occur with the windows version of `dotnet format`.

### Exceptions (if any)

### Further technical details
details of dotnet --info

.NET SDK:
Version: 10.0.105
Commit: a612c2a105
Workload version: 10.0.100-manifests.0793c108
MSBuild version: 18.0.11+a612c2a10

Runtime Environment:
OS Name: ubuntu
OS Version: 24.04
OS Platform: Linux
RID: ubuntu.22.04-x64
Base Path: /var/snap/dotnet/common/dotnet/sdk/10.0.105/

.NET workloads installed:
There are no installed workloads to display.
Configured to use workload sets when installing new manifests.
No workload sets are installed. Run "dotnet workload restore" to install a workload set.

Host:
Version: 10.0.5
Architecture: x64
Commit: a612c2a105

.NET SDKs installed:
10.0.105 [/var/snap/dotnet/common/dotnet/sdk]

.NET runtimes installed:
Microsoft.AspNetCore.App 10.0.5 [/var/snap/dotnet/common/dotnet/shared/Microsoft.AspNetCore.App]
Microsoft.NETCore.App 10.0.5 [/var/snap/dotnet/common/dotnet/shared/Microsoft.NETCore.App]

Other architectures found:
None

Environment variables:
DOTNET_INSTALL_DIR [/var/snap/dotnet/common/dotnet]

global.json file:
Not found

Learn more:
https://aka.ms/dotnet/info

Download .NET:
https://aka.ms/dotnet/download

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