[DDW-596] remove unused method instead of commenting it out

Author: DominikGuzei

source/renderer/app/containers/wallet/PaperWalletCreateCertificatePage.tsx

@@ -120,16 +120,6 @@ class PaperWalletCreateCertificatePage extends Component<Props, State> {
       currentStep: nextStep,
     });
   };
-  // onBack = () => {
-  //   // eslint-disable-next-line react/no-access-state-in-setstate
-  //   const prevStep = this.state.currentStep ? this.state.currentStep - 1 : 0;
-  //   const prevDialog = this.CREATE_CERTIFICATE_DIALOGS[prevStep];
-  //   this.setState({
-  //     currentStep: prevStep,
-  //   });
-  //   this.switchDialog(prevDialog);
-  //   this.props.actions.wallets.updateCertificateStep.trigger(true);
-  // };
   onClose = () => {
     this.setState({
       currentStep: 0,