Ensure plug-in registry has valid data when building image

[benoitf]

Is your enhancement related to a problem? Please describe.

Some releases had in the meta.yaml some images that did not exist.
It should not happen, release should break in case of invalid images

Describe the solution you'd like

Check that OCI images referenced by generated meta.yaml are valid

Describe alternatives you've considered

N/A

Additional context

Fail fast will guarantee that we're not pushing invalid resources.

[ericwill]

There could be a post-build step in the release that checks each meta.yaml for:

• valid sidecar, if one is defined
• valid icon
• valid repository
• valid vsix link

[ericwill]

Also, there is a script calling skopeo and fetching the digest -- we should make this part of the build process and fail the release if any of the digests/tags are invalid.

[sunix]

See eclipse-che/che-plugin-registry#814 (comment)
Should be fixed with eclipse-che/che-plugin-registry#815

[ericwill]

See eclipse/che-plugin-registry#814 (comment)
Should be fixed with eclipse/che-plugin-registry#815

Closing as the PR has been merged