The `name` & `version` attributes only existed in a previous form of
the API before it was switched over to using `fetchzip` &
`applyPatches`[1]. The attributes existed to be able to throw an
evaluation error with upgrade instructions when this was used. However,
this was before 22.11, so this shouldn't be in use anymore (and if
somebody is doing a migration from a very old NixOS, this is still
documented in the 22.11 release-notes[2]).
Anyways, this simplifies the code a little bit and also having both
`appName`/`appVersion` and `name`/`version` in there is quite confusing. But
still, I figured it's less confusing to not re-use attributes that were
deprecated in the past, hence the alternative naming.
[1] 3ca9b9a8ad
[2] d41b381310
9a62a46874