Logging in graders not working since v0.6.1

[Hapstyx]

Since Jagr v0.6.1, logging in graders using the gradle plugin is not possible and fails with the following message:

[23-Jun-20 15:11:31] [INFO] - Starting Jagr v0.9.0
[23-Jun-20 15:11:35] [ERROR] - Grader grader has 0 warnings and 2 errors
[23-Jun-20 15:11:35] [ERROR] - /p3/graph/BasicGraphTests.java:3 ERROR :: cannot access org.apache.logging.log4j.Logger
  bad class file: org.apache.logging.log4j.core.Logger
    class file contains wrong class: org.apache.logging.log4j.core.Logger
    Please remove or make sure it appears in the correct subdirectory of the classpath.
[23-Jun-20 15:11:35] [ERROR] - /p3/graph/BasicGraphTests.java:43 ERROR :: cannot find symbol
  symbol:   class Logger
  location: class p3.graph.BasicGraphTests
[23-Jun-20 15:11:35] [ERROR] - Grader container grader failed to load
[23-Jun-20 15:11:35] [INFO] - Submission container submission loaded
[23-Jun-20 15:11:35] [INFO] - Executor mode 'gradle' :: expected submission: 1
[23-Jun-20 15:11:41] [WARN] - No rubrics!

An example statement to reproduce the bug would be Jagr.Default.getInjector().getInstance(Logger.class).warn("Hello world!");