Set --experimental_collect_system_network_usage on MacOS CI workers.

It allows us to debug network issues more easily.

PiperOrigin-RevId: 638993614
Change-Id: Ic0f9a6b9021aa9c605a22877180734c471ade0d2
diff --git a/.bazelrc b/.bazelrc
index 89de37c..ca4cb7f 100644
--- a/.bazelrc
+++ b/.bazelrc
@@ -77,6 +77,7 @@
 ## For macOS
 common:ci-macos --config=ci-common
 build:ci-macos --repository_cache=/Users/buildkite/bazeltest/repo_cache
+build:ci-macos --experimental_collect_system_network_usage
 test:ci-macos --test_env=TEST_INSTALL_BASE=/Users/buildkite/bazeltest/install_base
 test:ci-macos --test_env=REPOSITORY_CACHE=/Users/buildkite/bazeltest/repo_cache
 test:ci-macos --test_env=REMOTE_NETWORK_ADDRESS=bazel.build:80