jobs/sync-stream-metadata: convert and sync release notes

Now that we have release notes in the streams repo, convert them from
YAML to JSON and sync them to S3 from which the website will fetch it
just like stream metadata.

jobs/sync-stream-metadata.Jenkinsfile

@@ -45,6 +45,16 @@ cosaPod(configMaps: ["fedora-messaging-cfg"], secrets: ["fedora-messaging-coreos
                     stream.metadata.update --stream ${stream}
                 """)
             }
+            // Currently, we always re-upload release notes. We don't want to
+            // falsely emit a stream.metadata.update message when only release
+            // notes changed, and also the way change detection works above
+            // doesn't mesh well with freshly regenerated data.
+            shwrap("""
+                python -c 'import sys, yaml, json; json.dump(yaml.safe_load(sys.stdin.read()), sys.stdout)' \
+                    < release-notes/${stream}.yaml > release-notes/${stream}.json
+                aws s3 cp --acl public-read --cache-control 'max-age=60' \
+                    release-notes/${stream}.json s3://fcos-builds/release-notes/${stream}.json
+            """)
         }
     }
 }