test: add test_log annotation to capture execution logs for issue #2023

This change annotates test_small_network_get_failure with test_log to
capture test execution logs in CI. The test passes locally but fails in
CI, and these logs will help us debug the issue.

Changes:
- Add test-log 0.2 to dev-dependencies in freenet-ping-app
- Replace manual logger setup with #[test_log::test] attribute
- Remove unused LevelFilter import
- Logs will now be captured and displayed on test failure

This will help us understand what's happening during CI test execution
and identify the root cause of issue #2023.

Author: claude

apps/freenet-ping/Cargo.lock

@@ -25,6 +25,7 @@ humantime = "2.2.0"
 
 [dev-dependencies]
 freenet = { path = "../../../crates/core" }
+test-log = "0.2"
 testresult = { workspace = true }
 
 [lib]

apps/freenet-ping/app/Cargo.toml

@@ -13,13 +13,12 @@ use futures::FutureExt;
 use testresult::TestResult;
 use tokio::{select, time::timeout};
 use tokio_tungstenite::connect_async;
-use tracing::{level_filters::LevelFilter, span, Instrument, Level};
+use tracing::{span, Instrument, Level};
 
 use common::{base_node_test_config, gw_config_from_path, APP_TAG, PACKAGE_DIR, PATH_TO_CONTRACT};
 
-#[tokio::test(flavor = "multi_thread")]
+#[test_log::test(tokio::test(flavor = "multi_thread"))]
 async fn test_small_network_get_failure() -> TestResult {
-    freenet::config::set_logger(Some(LevelFilter::INFO), None);
 
     const NUM_GATEWAYS: usize = 1;
     const NUM_NODES: usize = 3;