SPRINGFIELD — The chairwoman of the Illinois House Energy and Environment Committee said this week she will not hold hearings to examine what impact Commonwealth Edison’s lobbying and bribery practices have had on utility ratepayers, rebuffing a request from two Republican lawmakers.Instead, Rep. Ann Marie Williams, D-Chicago, said in a statement that she plans to introduce “tough new amendments” to the proposed Clean Energy Jobs Act next year “to ensure that we hold utilities accountable and take the politics out of …