HeartbeatTests.Integration_Cassandra_HeartbeatFailed is flaky

[Lorak-mmk]

Failing run: https://github.com/scylladb/cpp-rs-driver/actions/runs/19855928458/job/56894430328?pr=393

[ RUN ] HeartbeatTests.Integration_Cassandra_HeartbeatFailed
1764673526810 [DEBUG] (scylla_cpp_driver::logging:177) message: Log level is set to TRACE
ccm> ccm list
ccm> ccm list
ccm> ccm list
ccm> ccm stop
ccm> ccm status
ccm> ccm create --scylla -n 2:0 -i 127.0.0. --version=release:2025.2.2 -b cpp-driver_2025-2-2_2-0
ccm> ccm updateconf --rt=10000 read_request_timeout_in_ms:10000 write_request_timeout_in_ms:10000 request_timeout_in_ms:10000 phi_convict_threshold:16 hinted_handoff_enabled:false enable_materialized_views:true dynamic_snitch_update_interval_in_ms:1000 native_transport_max_threads:1 concurrent_reads:2 concurrent_writes:2 concurrent_compactors:1 compaction_throughput_mb_per_sec:0 key_cache_size_in_mb:0 key_cache_save_period:0 memtable_flush_writers:1 max_hints_delivery_threads:1 cas_contention_timeout_in_ms:10000 file_cache_size_in_mb:0
ccm> ccm start --wait-other-notice --wait-for-binary-proto --jvm_arg=--skip-wait-for-gossip-to-settle=0
ccm> ccm status
ccm> ccm node2 pause
ccm> ccm node2 resume
/home/runner/work/cpp-rs-driver/cpp-rs-driver/tests/src/integration/tests/test_heartbeat.cpp:102: Failure
ccm> ccm list
Expected: (metrics.stats.total_connections) < (initial_connections), actual: 3 vs 3
[ FAILED ] HeartbeatTests.Integration_Cassandra_HeartbeatFailed (70629 ms)