chore: upgrade to Gradle 6.8.1

[BlasiusSecundus]

No description provided.

[BlasiusSecundus]

The test failure is related to the test subscription:

Testing if usage errors are properly handled. > Should raise an assertion error if awaitAndGet methods are called after stop. FAILED
java.lang.IllegalStateException: The WebSocket session [2e] has been closed and no method (apart from close()) may be called on a closed session

Seems to be unrelated to the Gradle upgrade.

[oliemansm]

Thanks @BlasiusSecundus!