Bump go.opentelemetry.io/otel/sdk/metric from 1.20.0 to 1.21.0

Bumps [go.opentelemetry.io/otel/sdk/metric](https://github.com/open-telemetry/opentelemetry-go) from 1.20.0 to 1.21.0.
- [Release notes](https://github.com/open-telemetry/opentelemetry-go/releases)
- [Changelog](https://github.com/open-telemetry/opentelemetry-go/blob/main/CHANGELOG.md)
- [Commits](open-telemetry/opentelemetry-go@v1.20.0...v1.21.0)

---
updated-dependencies:
- dependency-name: go.opentelemetry.io/otel/sdk/metric
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

go.mod

@@ -20,10 +20,10 @@ require (
 	go.opentelemetry.io/collector/processor v0.89.0
 	go.opentelemetry.io/collector/receiver v0.89.0
 	go.opentelemetry.io/collector/service v0.89.0
-	go.opentelemetry.io/otel v1.20.0
+	go.opentelemetry.io/otel v1.21.0
 	go.opentelemetry.io/otel/exporters/prometheus v0.43.0
-	go.opentelemetry.io/otel/sdk v1.20.0
-	go.opentelemetry.io/otel/sdk/metric v1.20.0
+	go.opentelemetry.io/otel/sdk v1.21.0
+	go.opentelemetry.io/otel/sdk/metric v1.21.0
 	go.uber.org/multierr v1.11.0
 )
 
@@ -61,8 +61,8 @@ require (
 	github.com/yusufpapurcu/wmi v1.2.3 // indirect
 	go.opentelemetry.io/collector/confmap v0.89.0 // indirect
 	go.opentelemetry.io/collector/extension v0.89.0 // indirect
-	go.opentelemetry.io/otel/metric v1.20.0 // indirect
-	go.opentelemetry.io/otel/trace v1.20.0 // indirect
+	go.opentelemetry.io/otel/metric v1.21.0 // indirect
+	go.opentelemetry.io/otel/trace v1.21.0 // indirect
 	go.uber.org/goleak v1.2.1 // indirect
 	go.uber.org/zap v1.26.0 // indirect
 	golang.org/x/net v0.17.0 // indirect