Fixed password validation error messages in password change dialog

frontend/src/components/PasswordChangeDialog.vue

@@ -124,16 +124,16 @@ export default {
         })
         this.$emit('hide')
       }).catch(error => {
-      	if (error.response && error.response.status === 401) {
-      	  this.oldPasswordRejected = true
+        if (error.response && error.response.status === 401) {
+          this.oldPasswordRejected = true
           this.$refs.form.validate()
           return
-      	}
+        }
 
-      	if (error.response && error.response.status === 406) {
-          this.newPasswordErrors = error.response.data.new_password
+        if (error.response && error.response.data && error.response.data.newPassword) {
+          this.newPasswordErrors = error.response.data.newPassword
           return
-      	}
+        }
 
         this.errorAlert = error.toString()
       })