Eliminate outdated and unused copy of JGraphT library

Issue-Ref: 3478 Issue-Url: https://af3-developer.fortiss.org/issues/3478

Signed-off-by: Simon Barner barner@fortiss.org

mentioned in merge request af3!53 (merged)

mentioned in merge request exploration-alg!1 (merged)

added Code-Reviewed Verified labels

merged

mentioned in commit 2f67b204