Cannot successfully assign a ListViewItem to a specified group in PropertyGrid

* .NET Core Version:
5.0.100-preview.7.20311.17

* Have you experienced this same bug with .NET Framework?:
Yes

**Problem description:**
The setting is not successfully, the Group property was return to ‘(none)’ after clicking OK button.

**More Info:**
1. This issue is not a regression, can reproduce from .NET3.5 ~.NET4.8 in classic project and from .NET core 3.0 ~.NET 5.0 in Core project.
2. This issue is not reproducing when setting the Group property in designer properties window.

**Expected behavior:**
The Group property should be set successfully.

**Minimal repro:**
1. Create a Winforms core project.
2. Drag and drop a PropertyGrid and a ListView control to Form.
3. Add following code in InitializeComponent() part.
```cs
public Form1()
{
InitializeComponent();
propertyGrid1.SelectedObject = listView1; // <--
}
```
4. Build and run.
5. Add one `ListViewGroup` that Header is `Group1` by clicking the browser button next to the **Groups** property of ListView.
6. Add one `ListViewItem` that Text is `Item1` by clicking the browser button next to the **Items** property of ListView.
7. Find the **Group** property of the Item1, and set to ‘Group1’.
8. Click OK button in `ListViewItem` Collection Editor.

Or
1. Run the attached project. [SetGroupProperty.zip](https://github.com/dotnet/winforms/files/4769633/SetGroupProperty.zip)
2. Repeat the above step5~8.