message: test: trivial fix for deprecated runtime feature test.
  Noticed this while I was verifying that deprecated_by_default is handled
  consistently across proto binary/pb_text/JSON/YAML.
diff: @@ -859,8 +859,8 @@ TEST_P(ServerInstanceImplTest, BootstrapRtdsThroughAdsViaEdsFails) {
  TEST_P(ServerInstanceImplTest, DEPRECATED_FEATURE_TEST(InvalidLegacyBootstrapRuntime)) {
  EXPECT_THROW_WITH_MESSAGE(
  - initialize("test/server/test_data/server/invalid_runtime_bootstrap.yaml"), EnvoyException,
  - "Invalid runtime entry value for foo");
  + initialize("test/server/test_data/server/invalid_legacy_runtime_bootstrap.yaml"),
  + EnvoyException, "Invalid runtime entry value for foo");
  }
  // Validate invalid runtime in bootstrap is rejected.
  