Remove bogus override of ArgumentParser's error method (was accidentally left over from earlier experiment)
Remove bogus override of ArgumentParser's error method (was accidentally left over from earlier experiment)

yugangw-msft/azure-cli,BurtBiel/azure-cli,QingChenmsft/azure-cli,QingChenmsft/azure-cli,yugangw-msft/azure-cli,samedder/azure-cli,BurtBiel/azure-cli,QingChenmsft/azure-cli,samedder/azure-cli,yugangw-msft/azure-cli,samedder/azure-cli,yugangw-msft/azure-cli,QingChenmsft/azure-cli,yugangw-msft/azure-cli,samedder/azure-cli,yugangw-msft/azure-cli