tiny fixes contributors_guide.md
tiny fixes contributors_guide.md

bavc/avaa,rebeccaleung/avaa,kfrn/avaa,kfrn/avaa,rebeccaleung/avaa,kfrn/avaa,bavc/avaa,kellyhaydon/avaa,kellyhaydon/avaa,bavc/avaa,rebeccaleung/avaa,kellyhaydon/avaa