Next Thursday will mark the 25th anniversary of one Chicago law firm.However, after a quarter century, this will be the first year that the boutique labor and employment firm will be known officially as Franczek P.C. — rather than Franczek Radelet P.C., the firm name since 2009.The reason for the name change reflects the departure of David P. Radelet, who has joined Littler Mendelson P.C., along with three other Franczek partners, Christopher A. Johlie, Jeffrey S. Nowak and Staci Ketay Rotman.The new name is &ldquo …