Remove opencensus related vendored code

Author: khrm

go.mod

@@ -48,6 +48,7 @@ require (
 	github.com/sigstore/sigstore/pkg/signature/kms/hashivault v1.9.5
 	go.opentelemetry.io/otel v1.37.0
 	go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp v1.37.0
+	go.opentelemetry.io/otel/metric v1.37.0
 	go.opentelemetry.io/otel/sdk v1.37.0
 	go.opentelemetry.io/otel/trace v1.37.0
 	k8s.io/utils v0.0.0-20241210054802-24370beab758
@@ -126,7 +127,6 @@ require (
 	go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.37.0 // indirect
 	go.opentelemetry.io/otel/exporters/prometheus v0.59.1 // indirect
 	go.opentelemetry.io/otel/exporters/stdout/stdouttrace v1.37.0 // indirect
-	go.opentelemetry.io/otel/metric v1.37.0 // indirect
 	go.opentelemetry.io/otel/sdk/metric v1.37.0 // indirect
 	go.opentelemetry.io/proto/otlp v1.7.0 // indirect
 	go.yaml.in/yaml/v2 v2.4.2 // indirect
@@ -223,7 +223,7 @@ require (
 	github.com/vbatts/tar-split v0.12.1 // indirect
 	go.uber.org/automaxprocs v1.6.0 // indirect
 	go.uber.org/multierr v1.11.0 // indirect
-	golang.org/x/crypto v0.41.0
+	golang.org/x/crypto v0.41.0 // indirect
 	golang.org/x/mod v0.26.0 // indirect
 	golang.org/x/net v0.43.0 // indirect
 	golang.org/x/sync v0.16.0