[COST-5198] - split read traffic to read replica db using nginx proxy

[chambridge]

Jira Ticket

COST-5198

Description

This change will ...

• update nginx with HTTP method routing
• switch koku-api to koku-api-writes
• duplicate koku-api to koku-api-reads add a optional mounted secret for the read replica
• update clowder configurator to read from read replica secret if mounted and enabled via ENV var

Testing

1. Checkout the EE deployment
2. After the IQE tests have completed (you can look at the PR check), note that API request that went to the read or write api deployment
3. All test should pass as the API should default to use the clowder DB out of the box

Release Notes

• [ ] proposed release note

* [COST-5198](https://issues.redhat.com/browse/COST-5198) split read traffic to read replica db using nginx proxy