use correct word for button label

src/main/resources/i18n/strings.properties

@@ -159,7 +159,7 @@ hub.register.description=This is the first Hub access from this device. Please a
 hub.register.nameLabel=Device Name
 hub.register.invalidAccountKeyLabel=Invalid Account Key
 hub.register.occupiedMsg=Device already registered by another user
-hub.register.registerBtn=Confirm
+hub.register.registerBtn=Authorize
 ### Registration Success
 hub.registerSuccess.message=Device named
 hub.registerSuccess.description=To access the vault, your device needs to be authorized by the vault owner.