filter by drafts in the check step

The user now opts-in to getting final or draft releases. Default
behaviour is final releases.

NOTE: There is also strict filtering on only allowing semver supported tags.

Signed-off-by: David Jahn <david.a.jahn@gmail.com>

metadata.go

@@ -33,5 +33,19 @@ func metadataFromRelease(release *github.RepositoryRelease) []MetadataPair {
 		})
 	}
 
+	if release.TagName != nil {
+		metadata = append(metadata, MetadataPair{
+			Name:  "tag",
+			Value: *release.TagName,
+		})
+	}
+
+	if *release.Draft {
+		metadata = append(metadata, MetadataPair{
+			Name:  "draft",
+			Value: "true",
+		})
+	}
+
 	return metadata
 }