Password confirmation validation is not working after validate()

## Version 1.2.6

## Test Case
https://ember-twiddle.com/a83d4a0647b7705a3759e9688006be2d?openFiles=templates.components.marketing-copy.hbs%2C

## Steps to reproduce
Fill all the fields correctly and press "save" button 2 times

## Expected Behavior
all validations should be correct

## Actual Behavior
passwordConfirmation validation is failing and giving error:
Password confirmation doesn't match password