test/core should trigger c++ suite nowadays
diff --git a/tools/run_tests/python_utils/filter_pull_request_tests.py b/tools/run_tests/python_utils/filter_pull_request_tests.py
index 393aef8..56d6e4e 100644
--- a/tools/run_tests/python_utils/filter_pull_request_tests.py
+++ b/tools/run_tests/python_utils/filter_pull_request_tests.py
@@ -78,7 +78,7 @@
   '^src/python/': [_PYTHON_TEST_SUITE],
   '^src/ruby/': [_RUBY_TEST_SUITE],
   '^templates/': [],
-  '^test/core/': [_CORE_TEST_SUITE],
+  '^test/core/': [_CORE_TEST_SUITE, _CPP_TEST_SUITE],
   '^test/cpp/': [_CPP_TEST_SUITE],
   '^test/distrib/cpp/': [_CPP_TEST_SUITE],
   '^test/distrib/csharp/': [_CSHARP_TEST_SUITE],