CRD handling

[exu]

CRD is some kind of schema for data (CR)
in database world you will not remove whole table when migrating schema

IMO we need to start versioning it and make migrations of existing data between versions

e.g.
last update which added executor_type to Executor CRD
should have migration which adds “rest” for all executors (postman,cypress,curl)
we could have kubectl kubtest upgrade command which will handle your cluster upgrades