Bump google.golang.org/grpc in /_examples/remote-header

Bumps [google.golang.org/grpc](https://github.com/grpc/grpc-go) from 1.55.0 to 1.56.3.
- [Release notes](https://github.com/grpc/grpc-go/releases)
- [Commits](grpc/grpc-go@v1.55.0...v1.56.3)

---
updated-dependencies:
- dependency-name: google.golang.org/grpc
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <[email protected]>

_examples/remote-header/go.mod

@@ -16,7 +16,7 @@ require (
 	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/cespare/xxhash/v2 v2.2.0 // indirect
 	github.com/emirpasic/gods v1.18.1 // indirect
-	github.com/go-logr/logr v1.2.4 // indirect
+	github.com/go-logr/logr v1.3.0 // indirect
 	github.com/go-logr/stdr v1.2.2 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
 	github.com/golang/protobuf v1.5.3 // indirect
@@ -30,16 +30,16 @@ require (
 	github.com/prometheus/common v0.42.0 // indirect
 	github.com/prometheus/procfs v0.10.1 // indirect
 	github.com/twmb/murmur3 v1.1.6 // indirect
-	go.opentelemetry.io/otel v1.16.0 // indirect
+	go.opentelemetry.io/otel v1.21.0 // indirect
 	go.opentelemetry.io/otel/exporters/prometheus v0.39.0 // indirect
-	go.opentelemetry.io/otel/metric v1.16.0 // indirect
+	go.opentelemetry.io/otel/metric v1.21.0 // indirect
 	go.opentelemetry.io/otel/sdk v1.16.0 // indirect
 	go.opentelemetry.io/otel/sdk/metric v0.39.0 // indirect
-	go.opentelemetry.io/otel/trace v1.16.0 // indirect
+	go.opentelemetry.io/otel/trace v1.21.0 // indirect
 	golang.org/x/exp v0.0.0-20220518171630-0b5c67f07fdf // indirect
 	golang.org/x/net v0.17.0 // indirect
 	golang.org/x/sys v0.13.0 // indirect
 	golang.org/x/text v0.13.0 // indirect
-	google.golang.org/genproto v0.0.0-20230306155012-7f2fa6fef1f4 // indirect
-	google.golang.org/grpc v1.55.0 // indirect
+	google.golang.org/genproto v0.0.0-20230410155749-daa745c078e1 // indirect
+	google.golang.org/grpc v1.56.3 // indirect
 )