The previous code used `camelcase_to_underscore` to prettify the names for
display in the export preset, but it leads to inconsistencies if we don't make
sure to do the reverse operation when writing to the `AppxManifest.xml`.
It's simpler to keep the same names as in the manifest, which is also what
users will see referenced in MS documentation.
Fixes#47900.
Co-authored-by: Rémi Verschelde <rverschelde@gmail.com>