Fix ci failure issue

test/observability/observability_connection_metrics_test.h

@@ -481,6 +481,16 @@ inline void TestNetAcceptedIsMonotonic() {
             "reactor.net.connections.accepted");
 
         constexpr int N = 5;
+        // Send a real HTTP request and drain the response per connection.
+        // A bare connect+close races the accept dispatcher on slow CI
+        // runners — the RST can arrive before the accept callback fires,
+        // losing the +1 on `reactor.net.connections.accepted`. Driving a
+        // full request/response cycle forces the accept to complete
+        // before the close.
+        const std::string req =
+            "GET /h HTTP/1.1\r\n"
+            "Host: localhost\r\n"
+            "Connection: close\r\n\r\n";
         for (int i = 0; i < N; ++i) {
             int fd = ConnectTcp(port);
             if (fd < 0) {
@@ -489,15 +499,21 @@ inline void TestNetAcceptedIsMonotonic() {
                     TestFramework::TestCategory::OTHER);
                 return;
             }
-            // Open + immediately close. The accept-time +1 fires
-            // regardless of any later HTTP traffic.
+            if (!SendAll(fd, req)) {
+                ::close(fd);
+                TestFramework::RecordTest(TAG, false,
+                    "send failed at i=" + std::to_string(i),
+                    TestFramework::TestCategory::OTHER);
+                return;
+            }
+            (void)DrainSocket(fd, 500);
             ::close(fd);
-            std::this_thread::sleep_for(std::chrono::milliseconds(20));
         }
-        // Poll until the dispatcher drains the accept queue or 2 s elapse.
-        // A fixed 200 ms sleep is insufficient on slow CI runners.
+        // Poll for the counter to reach N — the accept-time bump runs on
+        // the dispatcher thread, so even after the response drains there
+        // is a small visibility gap before the Snapshot picks it up.
         {
-            auto deadline = std::chrono::steady_clock::now() + std::chrono::seconds(2);
+            auto deadline = std::chrono::steady_clock::now() + std::chrono::seconds(5);
             while (std::chrono::steady_clock::now() < deadline) {
                 auto snap_poll = fix.manager->meter_provider()->Snapshot();
                 double delta_poll = SumCounter(snap_poll,