Fix WeakPoint initializer in scan_bench: add missing test_context

benches/scan_bench.rs built a WeakPoint literal without the
`test_context` field added to the struct in v2.5.5, which broke
`cargo bench` (run by .github/workflows/e2e.yml) and any
`cargo check --all-targets`. Add `test_context: None`.

Verified with `cargo check --benches` (Finished, clean).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0196movYBRwNw8vkLRaaFoTu

Author: claude

benches/scan_bench.rs

@@ -203,6 +203,7 @@ fn bench_location_extraction(c: &mut Criterion) {
             description: "test".to_string(),
             recommended_attack: vec![],
             suppressed: false,
+            test_context: None,
         };
         100
     ];