Bump google.golang.org/grpc in /examples/demo/client

Bumps [google.golang.org/grpc](https://github.com/grpc/grpc-go) from 1.49.0 to 1.56.2.
- [Release notes](https://github.com/grpc/grpc-go/releases)
- [Commits](grpc/grpc-go@v1.49.0...v1.56.2)

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

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

examples/demo/client/go.mod

@@ -12,22 +12,22 @@ require (
 	go.opentelemetry.io/otel/metric v0.32.1
 	go.opentelemetry.io/otel/sdk v1.10.0
 	go.opentelemetry.io/otel/sdk/metric v0.31.0
-	google.golang.org/grpc v1.49.0
+	google.golang.org/grpc v1.56.2
 )
 
 require (
 	github.com/cenkalti/backoff/v4 v4.1.3 // indirect
 	github.com/felixge/httpsnoop v1.0.3 // indirect
 	github.com/go-logr/logr v1.2.3 // indirect
 	github.com/go-logr/stdr v1.2.2 // indirect
-	github.com/golang/protobuf v1.5.2 // indirect
+	github.com/golang/protobuf v1.5.3 // indirect
 	github.com/grpc-ecosystem/grpc-gateway/v2 v2.7.0 // indirect
 	go.opentelemetry.io/otel/exporters/otlp/internal/retry v1.10.0 // indirect
 	go.opentelemetry.io/otel/trace v1.10.0 // indirect
 	go.opentelemetry.io/proto/otlp v0.19.0 // indirect
-	golang.org/x/net v0.0.0-20210405180319-a5a99cb37ef4 // indirect
-	golang.org/x/sys v0.0.0-20210510120138-977fb7262007 // indirect
-	golang.org/x/text v0.3.5 // indirect
-	google.golang.org/genproto v0.0.0-20211118181313-81c1377c94b1 // indirect
-	google.golang.org/protobuf v1.28.1 // indirect
+	golang.org/x/net v0.9.0 // indirect
+	golang.org/x/sys v0.7.0 // indirect
+	golang.org/x/text v0.9.0 // indirect
+	google.golang.org/genproto v0.0.0-20230410155749-daa745c078e1 // indirect
+	google.golang.org/protobuf v1.30.0 // indirect
 )