message: test/test_common: fix comment about random seed flag
diff: @@ -32,7 +32,7 @@ namespace Envoy {
  }
  // Random number generator which logs its seed to stderr. To repeat a test run with a non-zero seed
  -// one can run the test with --test_arg=--gtest_filter=[seed]
  +// one can run the test with --test_arg=--gtest_random_seed=[seed]
  class TestRandomGenerator {
  public:
  TestRandomGenerator();
  