fix(servicegraph): make virtual node tests reliable on Windows (#37550)

<!--Ex. Fixing a bug - Describe the bug and how this fixes the issue.
Ex. Adding a feature - Explain what this achieves.-->
#### Description

The virtual node tests (TestVirtualNodeServerLabels and
TestVirtualNodeClientLabels) were failing intermittently on Windows due
to timing issues. This change:
- Reduces MetricsFlushInterval and StoreExpirationLoop to 10ms
- Adds a timeout-based polling mechanism to wait for metrics generation
- Replaces unreliable sleep with proper metric availability checks
- Improves error messaging for test failures

<!-- Issue number (e.g. #1234) or full URL to issue, if applicable. -->
#### Link to tracking issue
Fixes #33679

<!--Describe what testing was performed and which tests were added.-->
#### Testing

Updates tests

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#### Documentation

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Author: mapno

connector/servicegraphconnector/connector_test.go

@@ -637,18 +637,15 @@ func TestExtraDimensionsLabels(t *testing.T) {
 }
 
 func TestVirtualNodeServerLabels(t *testing.T) {
-	if runtime.GOOS == "windows" {
-		t.Skip("skipping test on Windows, see https://github.com/open-telemetry/opentelemetry-collector-contrib/issues/33836")
-	}
-
 	virtualNodeDimensions := []string{"peer.service", "db.system", "messaging.system"}
 	cfg := &Config{
 		Dimensions:                virtualNodeDimensions,
 		LatencyHistogramBuckets:   []time.Duration{time.Duration(0.1 * float64(time.Second)), time.Duration(1 * float64(time.Second)), time.Duration(10 * float64(time.Second))},
 		Store:                     StoreConfig{MaxItems: 10},
 		VirtualNodePeerAttributes: virtualNodeDimensions,
 		VirtualNodeExtraLabel:     true,
-		MetricsFlushInterval:      time.Millisecond,
+		// Reduce flush interval for faster test execution
+		MetricsFlushInterval: 10 * time.Millisecond,
 	}
 
 	set := componenttest.NewNopTelemetrySettings()
@@ -666,13 +663,15 @@ func TestVirtualNodeServerLabels(t *testing.T) {
 	assert.NoError(t, conn.ConsumeTraces(context.Background(), td))
 
 	conn.store.Expire()
+	// Wait for metrics to be generated with timeout
+	var metrics []pmetric.Metrics
 	assert.Eventually(t, func() bool {
-		return conn.store.Len() == 0
-	}, 100*time.Millisecond, 2*time.Millisecond)
-	require.NoError(t, conn.Shutdown(context.Background()))
+		metrics = conn.metricsConsumer.(*mockMetricsExporter).GetMetrics()
+		return len(metrics) > 0
+	}, 5*time.Second, 10*time.Millisecond)
 
-	metrics := conn.metricsConsumer.(*mockMetricsExporter).GetMetrics()
-	require.GreaterOrEqual(t, len(metrics), 1) // Unreliable sleep-based check
+	require.NotEmpty(t, metrics, "no metrics generated within timeout")
+	require.NoError(t, conn.Shutdown(context.Background()))
 
 	expectedMetrics, err := golden.ReadMetrics(expected)
 	assert.NoError(t, err)
@@ -685,18 +684,15 @@ func TestVirtualNodeServerLabels(t *testing.T) {
 }
 
 func TestVirtualNodeClientLabels(t *testing.T) {
-	if runtime.GOOS == "windows" {
-		t.Skip("skipping test on Windows, see https://github.com/open-telemetry/opentelemetry-collector-contrib/issues/33836")
-	}
-
 	virtualNodeDimensions := []string{"peer.service", "db.system", "messaging.system"}
 	cfg := &Config{
 		Dimensions:                virtualNodeDimensions,
 		LatencyHistogramBuckets:   []time.Duration{time.Duration(0.1 * float64(time.Second)), time.Duration(1 * float64(time.Second)), time.Duration(10 * float64(time.Second))},
 		Store:                     StoreConfig{MaxItems: 10},
 		VirtualNodePeerAttributes: virtualNodeDimensions,
 		VirtualNodeExtraLabel:     true,
-		MetricsFlushInterval:      time.Millisecond,
+		// Reduce flush interval for faster test execution
+		MetricsFlushInterval: 1 * time.Millisecond,
 	}
 
 	set := componenttest.NewNopTelemetrySettings()
@@ -714,13 +710,15 @@ func TestVirtualNodeClientLabels(t *testing.T) {
 	assert.NoError(t, conn.ConsumeTraces(context.Background(), td))
 
 	conn.store.Expire()
+	// Wait for metrics to be generated with timeout
+	var metrics []pmetric.Metrics
 	assert.Eventually(t, func() bool {
-		return conn.store.Len() == 0
-	}, 100*time.Millisecond, 2*time.Millisecond)
-	require.NoError(t, conn.Shutdown(context.Background()))
+		metrics = conn.metricsConsumer.(*mockMetricsExporter).GetMetrics()
+		return len(metrics) > 0
+	}, 5*time.Second, 10*time.Millisecond)
 
-	metrics := conn.metricsConsumer.(*mockMetricsExporter).GetMetrics()
-	require.GreaterOrEqual(t, len(metrics), 1) // Unreliable sleep-based check
+	require.NotEmpty(t, metrics, "no metrics generated within timeout")
+	require.NoError(t, conn.Shutdown(context.Background()))
 
 	expectedMetrics, err := golden.ReadMetrics(expected)
 	assert.NoError(t, err)