Investigate config map support

[glyn]

knative configures some images in config maps, e.g. here.

For comparison, kbld added some support for config maps such as this one which stores serialised JSON in a config map.

[bryanl]

This is a slippery slope. Config map data is opaque. For the second example to work, you have to know the data key, know that it is JSON data and then know particular paths in the data.

The first example is tenable. If you can detect ko URIs, then you can invoke ko when building the bundle archive or pushing it to a repository.