Allow running tests directly (default poller, foundry wont see them)
diff --git a/bazel/grpc_build_system.bzl b/bazel/grpc_build_system.bzl
index 2ef8544..bab66ac 100644
--- a/bazel/grpc_build_system.bzl
+++ b/bazel/grpc_build_system.bzl
@@ -87,7 +87,7 @@
     'linkopts': ["-pthread"],
   }
   if uses_polling:
-    native.cc_binary(testonly=True, **args)
+    native.cc_test(testonly=True, tags=['manual'], **args)
     for poller in POLLERS:
       native.sh_test(
         name = name + '@poller=' + poller,