bootc expects `org.opencontainers.image.version` to be set as a label, not an annotation

[fpoirotte]

Hello,

I stumbled across a minor issue with the way bootc looks for an image's version (when using bootc status).
It expects the version to be set as a label either with the key org.opencontainers.image.version or with the key version (see this function).

However, the OpenContainers image specification only defines org.opencontainers.image.version as a key inside annotations (see here).

To match the OpenContainers spec, would it be possible to change version_for_config to look for org.opencontainers.image.version in the annotations, then look for version in the labels, or would this be considered too much of a breaking change?

Best regards,
François