[Testnet Comp] Replace deprecated Program payload in transaction with Script

• The Program payload in transaction has been deprecated and had to be replaced by Script
• Detailed information about the changes: https://developers.libra.org/blog/2019/10/22/simplifying-payloads

As jlibra is a library, the release method is a Maven artefact: https://repo1.maven.org/maven2/dev/jlibra/