Field does not contain a type "xdm:condition" in discount schema

## What are the schemas that are affected by the issue
xdm/schemas/data/discount.schema.json

## What are examples of products that are impacted by the issue
none, not used currently.

Type attribute missing. It is not clear what it would be.
```
"xdm:condition": {
"title": "Condition",
"description":
"The minimum amount of items or price for the dicount to qualify"
}
```

Start with xdm/schemas/data/discount.schema.json and inspect nearby schema fields and their type declarations to determine the convention for xdm:condition. Confirm the appropriate type for the condition field, then validate that the schema remains valid and that the field definition clearly describes its expected value.

Written by the indexing model from the issue text.