Kafka integration test `drains_acknowledgements_during_rebalance_sticky_assignments` is flaky

[pront]

Sample failure:

running 1 test
thread 'sources::kafka::integration_test::drains_acknowledgements_during_rebalance_sticky_assignments' panicked at src/sources/kafka.rs:2130:9:
assertion `left == right` failed
  left: 127357
 right: 125000
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
test sources::kafka::integration_test::drains_acknowledgements_during_rebalance_sticky_assignments ... FAILED
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     Summary [ 143.965s] 30 tests run: 29 passed, 1 failed, 1107 skipped
  TRY 4 FAIL [  15.112s] vector sources::kafka::integration_test::drains_acknowledgements_during_rebalance_sticky_assignments
error: test run failed
Error: command: CONFIG_VECTOR_IMAGE="vector-test-runner-1.77.2:latest" CONFIG_VERSION="latest" KAFKA_HOST="kafka" TEST_LOG="info" "docker" "exec" "--tty" "--env" "CARGO_BUILD_TARGET_DIR=/home/target" "--env" "CONFIG_VECTOR_IMAGE" "--env" "CONFIG_VERSION" "--env" "KAFKA_HOST" "--env" "TEST_LOG" "vector-test-runner-1.77.2" "cargo" "nextest" "run" "--no-fail-fast" "--no-default-features" "--features" "all-integration-tests" "--lib" "::kafka::" "--no-capture" "--retries" "3"
  failed with exit code: 100

It worth exploring if we can relax this condition.