[HDPI]A form with FormBorderStyle=FixedDialog and ControlBox=false is sized incorrectly

* .NET Core Version:
.NET SDK 6.0.100-preview.6.21313.2

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

**More info:**
There is a similar VSO bug: [631474](https://devdiv.visualstudio.com/DevDiv/_workitems/edit/631474).

**Actual behavior:**
The form is truncated at the bottom.

**Expected behavior:**
Form should look the same way as in the designer.

**Minimal repro:**
1. Create a Winforms core application in 100% DPI mode.
2. In the Form’s properties, set the FormBorderStyle = FixedDialog and ControlBox = false.
3. Adding some controls(such as Button) near the bottom of the form.
4. Declare compatibility with Window 10 in app.manifest:
5. Set Windows DPI as 300%, build and run the application, then observe the form size.

Or
1. Set Windows DPI as 300%.
2. Open the attached application.
[WinFormsApp4.zip](https://github.com/dotnet/winforms/files/6661589/WinFormsApp4.zip)
3. Build and run it, then observe the form size.