Illegal reflective access warnings on JDK 11

[guaranadev]

When using JDK 11 and Gradle 6.0.1

WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by pl.pojo.tester.internal.utils.FieldUtils ([LOCAL_JAR_PATH]) to field java.lang.reflect.Field.modifiers
WARNING: Please consider reporting this to the maintainers of pl.pojo.tester.internal.utils.FieldUtils
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release