Jeon Soyeon of Cube Entertainment has finally made her debut! The soloist dropped her single “Jelly” along with the music video earlier this evening. The track was co-written by Jeon Soyeon and Flow Blow and gives an expression of happiness that feels like being on top of jelly. Jeon Sooyeon was formely on “Produce 101” and “Unpretty Rapstar 3” which…