awstranscriber: fix what we send over for translations

Prior to this commit, we were sending over words concatenated together with no separators, for instance "Idon'twanttobeanemperor".

The translation service seems clever enough to translate the contents anyway, but there is no reason to make its task harder than necessary, and it didn't re-add separators when the target language was the same as the source language, which resulted in less than ideal output.