Konnect entities: support Route JSON/expressions API change

[pmalek]

Problem Statement

https://github.com/Kong/kong-admin-spec-generator/pull/40 and then subsequently https://github.com/Kong/platform-api/pull/973, introduced a change in Konnect API, where users can use a separate route API to create expressions routes.

This had breaking consequences on the sdk konnect go Kong/sdk-konnect-go#75 which this project uses.

This issue tracks refining the CRD types, so that users can choose either JSON or expression routes when creating routes via CRD

Proposed Solution

Additional Information

Acceptance Criteria

• As a user, I can choose which type of route (JSON or expressions) will be created on Konnect when I use the KongRoute.