Adds -Djunit.platform.reporting.open.xml.enabled=true -Djunit.platform.reporting.open.xml.socket=port to the JAVA_TOOL_OPTIONS environment variable of the enclosed steps, so that test JVMs stream their results without any change to the build. Every JVM started in the block sees the variable (and prints a Picked up JAVA_TOOL_OPTIONS message), but only JUnit Platform test runs act on it.

Uncheck to configure the test JVMs yourself, using the port from the JUNIT_OTR_SOCKET_PORT environment variable, e.g. mvn test -Djunit.platform.reporting.open.xml.enabled=true -Djunit.platform.reporting.open.xml.socket=$JUNIT_OTR_SOCKET_PORT.