Bump golang.org/x/net in /exporter/splunkhecexporter

Bumps [golang.org/x/net](https://github.com/golang/net) from 0.21.0 to 0.23.0.
- [Commits](golang/net@v0.21.0...v0.23.0)

---
updated-dependencies:
- dependency-name: golang.org/x/net
  dependency-type: indirect
...

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

exporter/splunkhecexporter/go.mod

@@ -104,8 +104,8 @@ require (
 	go.opentelemetry.io/otel/sdk/metric v1.24.0 // indirect
 	golang.org/x/exp v0.0.0-20230711023510-fffb14384f22 // indirect
 	golang.org/x/mod v0.14.0 // indirect
-	golang.org/x/net v0.21.0 // indirect
-	golang.org/x/sys v0.17.0 // indirect
+	golang.org/x/net v0.23.0 // indirect
+	golang.org/x/sys v0.18.0 // indirect
 	golang.org/x/text v0.14.0 // indirect
 	golang.org/x/tools v0.15.0 // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20240123012728-ef4313101c80 // indirect