test_graph: add filename only to pdf list (#3972)

The pdfs list should be constructed from filenames only without other path components, i.e. use last entry from split()

tests/analysis/test_graphs.py

@@ -373,7 +373,7 @@ def test_draw(self):
         bc_square_sg_r.draw_graph_to_file(f"{self.tmp_path}/bc_square_r.pdf", algo="neato", image_labels=False)
 
         # ensure PDF files were created
-        pdfs = {path.split("/") for path in glob(f"{self.tmp_path}/*.pdf")}
+        pdfs = {path.split("/")[-1] for path in glob(f"{self.tmp_path}/*.pdf")}
         expected_pdfs = {
             "bc_square_r_single.pdf",
             "bc_square_r.pdf",