bug fix: ErrorPathClassifier no longer returns a path that ends in an assume edge (without successor), but instead returns the full path; the AssumptionUseDefinitionCollector did not work after that change; fixed

git-svn-id: https://svn.sosy-lab.org/software/cpachecker/trunk@14646 4712c6d2-40bb-43ae-aa4b-fec3f1bdfe4c