What is the legality of using one line from the TV show Workaholics in a song that would be released and could make profit?

Are you going to repeat the line or play the recording from the show itself? Would someone recognize that is was from that television show? Using someone else's copyrighted work, even a recognizable portion of the work, is copyright infringement. I would think that the copyright in the television show has been registered. There is no minimum amount of someone else's work that you can safely use - that is a myth. You would need to determine if your use is a "fair use" which is a judgment call. Even if you get professional advice, a court may not agree with your conclusion. You may want to contact the owner of the copyright in the show to see if they will give you a license. Otherwise you risk copyright infringement.