chore: rm two unused lines

[maelle]

even if we don't use the code, to get a clean Jarl pass

[github-actions]

This is how benchmark results would change (along with a 95% confidence interval in relative change) if c5bdb37 is merged into main:

• ✔️as_adjacency_matrix: 806ms -> 812ms [-0.88%, +2.52%]
• ✔️as_biadjacency_matrix: 800ms -> 794ms [-2.67%, +1.36%]
• ✔️as_data_frame_both: 1.52ms -> 1.54ms [-2.38%, +5.32%]
• ✔️as_long_data_frame: 3.91ms -> 3.88ms [-2.64%, +1.05%]
• ✔️es_attr_filter: 3.02ms -> 3.02ms [-2.82%, +2.31%]
• ✔️graph_from_adjacency_matrix: 121ms -> 122ms [-1.29%, +3.02%]
• ✔️graph_from_data_frame: 3.37ms -> 3.36ms [-2.51%, +2.21%]
• ✔️vs_attr_filter: 1.71ms -> 1.73ms [-1.51%, +4.16%]
• ✔️vs_by_name: 1.11ms -> 1.12ms [-1.68%, +3.59%]
  Further explanation regarding interpretation and methodology can be found in the documentation.