Avoid saving rules and rewards with missing data

[bjarnef]

Describe the bug
At the moment it is possible to add rules and rewards and click "Save and close" without selecting further details about the rule or reward.

Steps To Reproduce
Steps to reproduce the behavior:

1. Go to Commerce section and select a store.
2. Click on 'Discounts' node.
3. Click on 'Create Discount'
4. Add a Rule or Reward
5. Select and Rule/Rule type and click "Save and close".
6. Note the rule/reward being listed, but with missing data.

Expected behavior
I think the button "Save and close" should be disabled or at least validation of required properties to be selected and being validated on submit. It would also help to mark required properties using asterisk (*).

Screenshots

Vendr version:
Vendr v0.1.0-alpha0346

[bjarnef]

@mattbrailsford I noticed this in Vendr v1.1.3 as well. Maybe the rule/reward dialog always should validate the properties are filled, e.g Price Type and Adjustment.