Add a TTL for Review Apps

[mms-gianni]

Description

Review Apps are apps that were created by opening a PR. these review Apps should have an optional Time To Live (TTL).

The TTL should be defined by every pipeline. A default should be to let the apps live forever (to keep the backward compatibility). The TTL should be set when creat

Possible solution

Add a new input field here

Alternatives

No response

Additional information

This will require changes in the Operator to to handle this field. It is not clear, who or what will remove these apps. Probably a periodic cronjob within the kubero namespace, which calls an API endpoint on the kubero UI container.