(Refiles to remove extraneous words before first bullet point) By Francesco Canepa and Valentina Za FRANKFURT, June 23 (Reuters) - The European Central Bank secured key parliamentary backing on Tuesday for the launch of a digital euro, an electronic means of payments aimed at making the euro zone less reliant on U.S. credit cards at a ‌time of fraying transatlantic relationships. The digital euro, essentially an electronic wallet guaranteed by the central bank...