Import Settings popup: pressing Enter right after editing Scale doesn't "take" the new value

[JoeyQuint]

Describe the Bug

In the Import settings window: when typing something in the "Scale" value and confirming directly with the "Enter" key, the new value isn't processed (so the object will be imported with the "initial scale").

To reproduce

Let's say you want to import an object in WadTool, from an external software.

1. Open the Skeleton Editor for the object.
2. Click Import Mesh.
3. Select the file you want to import.
4. In the "Import Settings" popup:
   1. Place the cursor in the "Scale" field. Let's say the current value is 1024.
   2. Edit the value. For example, replace it by 512.
   3. Without clicking anywhere else, press Enter on your keyboard.
      -> The window closes and the object is imported, but at the "initial scale" (in this example, 1024).

Now you repeat step 4, but rather than pressing Enter at 4.3:

• Either click on Ok - or any other button, or any checkbox (ie. anything you can interact with, even the Minimize and Close buttons)
• Or press Tab to switch to another field (then press enter or click Ok)
  Then you will "see" that it's taken into account because the "Preset" field switches to "Custom Preset", and most importantly once the object will be imported at the scale you typed.

Notes:

• I suspected the same behavior would occurred when you used Space to check/uncheck a checkbox, or using Up&Down (or the mousewheel) on the Preset field.
  But actually, the window reacts normally with those. It's only the Scale field which has this issue.
• I don't know if this was happening with the previous (non-WPF) version of this window.

Expected Behaviour

When you press Enter, it should act as if you clicked Ok: take the value into account.
(and in theory, it should trigger any other behavior first, like detecting this is now another preset - even though this actually won't have any impact)