Previously the target locale of a translation file had to be extracted
from the contents of the translation file. Therefore it was an error if
the translation file did not provide a target locale.
Now an array of locales can be provided via the `translationFileLocales`
option that overrides any target locale extracted from the file.
This allows us to support translation files that do not have a target
locale specified in their contents.
// FW-1644
Fixes#33323
PR Close#33381