rebase: bump google.golang.org/grpc from 1.66.0 to 1.66.2

Bumps [google.golang.org/grpc](https://github.com/grpc/grpc-go) from 1.66.0 to 1.66.2.
- [Release notes](https://github.com/grpc/grpc-go/releases)
- [Commits](https://github.com/grpc/grpc-go/compare/v1.66.0...v1.66.2)

---
updated-dependencies:
- dependency-name: google.golang.org/grpc
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

vendor/google.golang.org/grpc/experimental/stats/metricregistry.go

@@ -20,7 +20,6 @@ package stats
 
 import (
 	"maps"
-	"testing"
 
 	"google.golang.org/grpc/grpclog"
 	"google.golang.org/grpc/internal"
@@ -250,9 +249,9 @@ func RegisterInt64Gauge(descriptor MetricDescriptor) *Int64GaugeHandle {
 }
 
 // snapshotMetricsRegistryForTesting snapshots the global data of the metrics
-// registry. Registers a cleanup function on the provided testing.T that sets
-// the metrics registry to its original state. Only called in testing functions.
-func snapshotMetricsRegistryForTesting(t *testing.T) {
+// registry. Returns a cleanup function that sets the metrics registry to its
+// original state.
+func snapshotMetricsRegistryForTesting() func() {
 	oldDefaultMetrics := DefaultMetrics
 	oldRegisteredMetrics := registeredMetrics
 	oldMetricsRegistry := metricsRegistry
@@ -262,9 +261,9 @@ func snapshotMetricsRegistryForTesting(t *testing.T) {
 	maps.Copy(registeredMetrics, registeredMetrics)
 	maps.Copy(metricsRegistry, metricsRegistry)
 
-	t.Cleanup(func() {
+	return func() {
 		DefaultMetrics = oldDefaultMetrics
 		registeredMetrics = oldRegisteredMetrics
 		metricsRegistry = oldMetricsRegistry
-	})
+	}
 }