Motivation:
The entire optaplanner website and get started experience is aimed at convincing users to clone the optaplanner-quickstarts repo and play with it locally. If that doesn't work, for whatever reason, we should know about it immediately and automatically. Recently it was broken for 5 days and the issue was discovered by luck.

Requirements:

• nightly job (at least once every 24 hours)
• git clone optaplanner-quickstarts
• mvn clean install it. Using an empty maven repo.
  • Jboss nexus must NOT be in the settings.xml etc. It's not in the pom.xml.
• Send any errors to Zulip channel optaplanner-dev to topic "Failed nightly build".