Immutable Empty List: subList always throwing IndexOutOfBoundsException

ImmutableListImpl.EmptyList.subList(int fromIndex, int toIndex) should return ImmutableListImpl.empty() when fromIndex = toIndex = 0 instead of throwing IndexOutOfBoundsException.

https://git.floragunn.com/util/fluent-collections/-/blob/main/src/main/java/com/floragunn/fluent/collections/ImmutableListImpl.java?ref_type=heads#L1165