build failure

It seems to be related to JMC-6595, "mvn clean package" failed with the following error:

[ERROR] Failed to resolve target definition openjdk/jmc/releng/platform-definitions/platform-definition-2019-09/platform-definition-2019-09.target: Failed to load p2 metadata repository from location https://archive.eclipse.org/technology/babel/update-site/R0.17.0/2019-06/: Unable to read repository at https://archive.eclipse.org/technology/babel/update-site/R0.17.0/2019-06/content.xml. Received fatal alert: handshake_failure -> [Help 1]