wizardview: clear username line edit when clicking on skip button

It is to prevent using the text in username line edit to create an account
when the user does not want to register it.

Change-Id: Icae024a82141ea06dd6b4c5413de2ad9725433b5

src/wizardview/components/CreateAccountPage.qml

@@ -209,8 +209,11 @@ Rectangle {
                     pressedColor: JamiTheme.buttonTintedGreyPressed
                     outlined: true
 
-                    onClicked: createAccountStack.currentIndex =
-                               createAccountStack.currentIndex + 1
+                    onClicked: {
+                        usernameEdit.clear()
+                        createAccountStack.currentIndex =
+                                createAccountStack.currentIndex + 1
+                    }
                 }
 
                 AccountCreationStepIndicator {