Cannot reduce cell padding in DataGrid

[rick-palmsens]

Describe the bug

I am unable to remove the padding in cells. I am however able to remove the padding in the column headers.

Steps to Reproduce

Steps to reproduce the behavior:

1. Create a new WinUI App
2. Add DataGrid to MainWindow.xaml:

<Window
    x:Class="DataGridStyling.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:DataGridStyling"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:controls="using:CommunityToolkit.WinUI.UI.Controls"
    xmlns:primitives="using:CommunityToolkit.WinUI.UI.Controls.Primitives"
    mc:Ignorable="d">

    <controls:DataGrid HorizontalAlignment="Stretch"
                       VerticalAlignment="Stretch"
                       AutoGenerateColumns="True"
                       GridLinesVisibility="All"
                       RowHeight="1"
                       ItemsSource="{x:Bind _collection}">

        <controls:DataGrid.ColumnHeaderStyle>
            <Style TargetType="primitives:DataGridColumnHeader">
                <Setter Property="MinWidth" Value="0"/>
                <Setter Property="MinHeight" Value="0"/>
                <Setter Property="Padding" Value="0"/>
                <Setter Property="Margin" Value="0"/>
            </Style>
        </controls:DataGrid.ColumnHeaderStyle>
        <controls:DataGrid.RowStyle>
            <Style TargetType="controls:DataGridRow">
                <Setter Property="MinWidth" Value="0"/>
                <Setter Property="MinHeight" Value="0"/>
                <Setter Property="Padding" Value="0"/>
                <Setter Property="Margin" Value="0"/>
            </Style>
        </controls:DataGrid.RowStyle>
        <controls:DataGrid.CellStyle>
            <Style TargetType="controls:DataGridCell">
                <Setter Property="MinWidth" Value="0"/>
                <Setter Property="MinHeight" Value="0"/>
                <Setter Property="Padding" Value="0"/>
                <Setter Property="Margin" Value="0"/>
            </Style>
        </controls:DataGrid.CellStyle>
    </controls:DataGrid>
</Window>

3. Add data to the DataGrid in MainWindow.cs:

using Microsoft.UI.Xaml;
using System.Collections.ObjectModel;

// To learn more about WinUI, the WinUI project structure,
// and more about our project templates, see: http://aka.ms/winui-project-info.

namespace DataGridStyling
{
    /// <summary>
    /// An empty window that can be used on its own or navigated to within a Frame.
    /// </summary>
    public sealed partial class MainWindow : Window
    {
        public MainWindow()
        {
            this.InitializeComponent();

            for (int i = 0; i < 100; ++i)
            {
                _collection.Add(new Foo
                {
                    X = i,
                    Y = i * i,
                    Z = i * i * i,
                });
            }
        }

        class Foo
        {
            public int X { get; set; }
            public int Y { get; set; }
            public int Z { get; set; }
        }


        private ObservableCollection<Foo> _collection = new();
    }

}

4. Compile and run the application
5. See this:
   

Expected behavior

The row padding should be removed by the styles just like it was removed in the headers.

Environment

NuGet Package(s):

<PackageReference Include="CommunityToolkit.WinUI" Version="7.0.3" />
<PackageReference Include="CommunityToolkit.WinUI.UI.Controls.DataGrid" Version="7.0.3" />
<PackageReference Include="Microsoft.ProjectReunion" Version="0.8.4" />
<PackageReference Include="Microsoft.ProjectReunion.Foundation" Version="0.8.4" />
<PackageReference Include="Microsoft.ProjectReunion.WinUI" Version="0.8.4" />

Package Version(s):

Windows 10 Build Number:

• Fall Creators Update (16299)
• April 2018 Update (17134)
• October 2018 Update (17763)
• May 2019 Update (18362)
• May 2020 Update (19041)
• October 2020 Update (19042)

App min and target version:

• Fall Creators Update (16299)
• April 2018 Update (17134)
• October 2018 Update (17763)
• May 2019 Update (18362)
• May 2020 Update (19041)
• Insider Build ({build_number})

Device form factor:

• Desktop
• Xbox
• Surface Hub
• IoT

Visual Studio version:

• 2017 (15.{minor_version})
• 2019 (16.11.2)
• 2022 (17.{minor_version})

Hello rick-palmsens, thank you for opening an issue with us!

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