rebase: bump google.golang.org/grpc from 1.68.0 to 1.68.1

Bumps [google.golang.org/grpc](https://github.com/grpc/grpc-go) from 1.68.0 to 1.68.1.
- [Release notes](https://github.com/grpc/grpc-go/releases)
- [Commits](https://github.com/grpc/grpc-go/compare/v1.68.0...v1.68.1)

---
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/internal/resolver/dns/dns_resolver.go

@@ -237,7 +237,9 @@ func (d *dnsResolver) watcher() {
 }
 
 func (d *dnsResolver) lookupSRV(ctx context.Context) ([]resolver.Address, error) {
-	if !EnableSRVLookups {
+	// Skip this particular host to avoid timeouts with some versions of
+	// systemd-resolved.
+	if !EnableSRVLookups || d.host == "metadata.google.internal." {
 		return nil, nil
 	}
 	var newAddrs []resolver.Address