chore(deps): update module go.opentelemetry.io/contrib/propagators/b3 to v1.21.1

Author: renovate[bot]

go.mod

@@ -8,7 +8,7 @@ require (
 	github.com/spf13/pflag v1.0.5
 	github.com/spf13/viper v1.15.0
 	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.37.0
-	go.opentelemetry.io/contrib/propagators/b3 v1.12.0
+	go.opentelemetry.io/contrib/propagators/b3 v1.21.1
 	go.opentelemetry.io/otel v1.11.2
 	go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.11.2
 	go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.11.2