Enhance Credit Card Fraud Recipe: Give example source connector

I think the credit card fraud recipe would benefit from having an example source connector. Our technical marketing demo for database modernization does this with Oracle CDC:
- https://github.com/confluentinc/demo-database-modernization/blob/master/confluent/example_oracle_cdc.json

There is a small issue when doing this -- you will get a "column name already exists" when creating the customers table because the connector will set a json record key called `id`. So you would have to rename the field and do something like this:

```sql
CREATE TABLE FD_CUSTOMERS (
customer_id DOUBLE PRIMARY KEY
) WITH (KAFKA_TOPIC = 'ORCL.ADMIN.CUSTOMERS',KEY_FORMAT='JSON',VALUE_FORMAT = 'JSON_SR');
```

All subsequent references to the field would have to be updated too.

For more information, see
- https://github.com/confluentinc/demo-database-modernization/issues/5

Start with the linked confluent/example_oracle_cdc.json example and locate the credit card fraud recipe in this repository. Add an example source connector, account for the renamed customer_id field in the table definition and subsequent references, and verify that the recipe can create and use the customers table.

Written by the indexing model from the issue text.