Update phoible-references.bib

[inigourrestarazu]

I spotted a typo in the sections of a book, West African Language Data Sheets.

It says Langauge, instead of Language. I also found it in another reference of a Bantu language. I replace all of them

[bambooforest]

@inigourrestarazu -- many thanks for this. and @LinguList for sending it this way.