The option for A4 is separated from the other A* page sizes in the Page Format option in Document Properties
#### Summary:
When we open the dropdown menu for selecting the page format in document properties, the A4 page size is listed at the very top, while the A3 and A5 sizes are grouped together.
#### Steps to reproduce:
1. Open Inkscape
2. Open the Document Properties (<kbd>File</kbd> -> <kbd>Document Properties...</kbd>)
3. Under the heading **Front Page**, open the **Format:** dropdown.
#### What happened?
The A4 option isn't grouped with the rest of the A* sizes in the document properties.
#### What should have happened?
If the A4 size was grouped, it would be easier to find.
Sample attachments:

#### Version info
Inkscape 1.3-alpha (2a5ddc9d23, 2023-03-29)
GLib version: 2.76.1
GTK version: 3.24.38
glibmm version: 2.66.6
gtkmm version: 3.24.7
libxml2 version: 2.10.3
libxslt version: 1.1.37
Cairo version: 1.17.7
Pango version: 1.50.14
HarfBuzz version: 7.1.0
OS version: Windows 10 22H2
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issue