Generated UFOs missing weight in fontinfo (fontmake 3.4.0)

`fontmake -o ufo -g Inter-Roman.glyphs` produces UFOs which are missing `openTypeOS2WeightClass` entries in fontinfo. The generated designspace file is correct and contains weight data.

Repro: (unzip attached glyphs source: [Inter-Roman.glyphs.zip](https://github.com/googlefonts/fontmake/files/9717422/Inter-Roman.glyphs.zip))

```
$ fontmake -o ufo -g Inter-Roman.glyphs
INFO:fontmake.font_project:Building master UFOs and designspace from Glyphs source
INFO:glyphsLib.classes:Parsing "Inter-Roman.glyphs" file into
$ grep -i weight master_ufo/Inter-*.ufo/fontinfo.plist
# no results
$ grep -i weight master_ufo/Inter.designspace

























$
```

```
$ fontmake --version
3.4.0
$ python --version
Python 3.10.6
```