SpecialPageAliasTest: Fix arguments of Language::fetchLanguageNames

SpecialPageAliasTest: Fix arguments of Language::fetchLanguageNames

Language::fetchLanguageNames( 'mwfile' ) means all languages with the
default filter 'mw' and names in the language 'mwfile'.

Language::fetchLanguageNames( null, 'mwfile' ) means language all
languages with the filter 'mwfile' and names in the default language.

This change removes the test for the language codes:
* aa
* als
* bat-smg
* be-x-old
* cho
* fiu-vro
* ho
* hz
* kj
* kr
* mh
* mus
* ng
* no
* rn
* roa-rup
* shi-latn
* shi-tfng
* simple
* tum
* uz-cyrl
* uz-latn
* zh-classical
* zh-min-nan
* zh-yue

Change-Id: I7266a67e37862daf863d1565d84cfeebaf5cb680