Any firefighter’s civil service commission hereafter created pursuant to the provisions of this chapter, except where such civil service commission has been continuously in operation for eight years or more, may be discontinued and abolished as follows: A petition signed by 25 percent of the number of legal voters voting at the last general municipal election, shall be filed with the governing body of such city and request that the following question be submitted to the voters: “Shall the firefighter’s civil service commission be abolished?”