release: don't ostree commits into release metadata on f43+

Starting in f43, we won't be publishing content to the OSTree repo
anymore, so there's no point in having any commit hash in the release
metadata.

On builds that have `oci-imported: true`, let's stop adding the `commit`
key in the release metadata in `cosa generate-release-metadata`. That'll
naturally bind it to f43.

In plume, handle the case where there is no commit string.

Author: jlebon

mantle/cmd/plume/release.go

@@ -299,10 +299,12 @@ func modifyReleaseMetadataIndex(api *aws.API, rel release.Release) {
 	var commits []release.IndexReleaseCommit
 	var pullspecs []release.IndexReleaseOciImage
 	for arch, vals := range rel.Architectures {
-		commits = append(commits, release.IndexReleaseCommit{
-			Architecture: arch,
-			Checksum:     vals.Commit,
-		})
+		if vals.Commit != "" {
+			commits = append(commits, release.IndexReleaseCommit{
+				Architecture: arch,
+				Checksum:     vals.Commit,
+			})
+		}
 		pullspecs = append(pullspecs, release.IndexReleaseOciImage{
 			Architecture:   arch,
 			ContainerImage: *vals.OciImage,

src/cmd-generate-release-meta

@@ -146,7 +146,8 @@ def append_build(out, input_):
     print(f"  {arch} images:")
     # build the architectures dict
     arch_dict = {"media": {}}
-    ensure_dup(input_, arch_dict, "ostree-commit", "commit")
+    if not input_.get('coreos-assembler.oci-imported'):
+        ensure_dup(input_, arch_dict, "ostree-commit", "commit")
 
     # within the CoreOS pipelines, we always expect base-oscontainer to be set,
     # but this script is also currently used by OKD but they only care about