There is some code at assignment_hash_map.cu (link) that has the following line:
RAFT_CHECK_CUDA(handle_ptr->get_stream());
The issue is that there is no handle_ptr variable in the context this was called, it should be solution.handle_ptr. Either there is a global variable somewhere called handle_ptr (probably a bad idea), or RAFT_CHECK_CUDA is never activated on continuous integration.