Fix example packages

example/dice/doc.go → example/dice/main.go

@@ -5,3 +5,6 @@
 //
 // Deprecated: Examples are moved to https://github.com/open-telemetry/opentelemetry-go-contrib.
 package main
+
+func main() {
+}

example/namedtracer/doc.go → example/namedtracer/main.go

@@ -5,3 +5,6 @@
 //
 // Deprecated: Examples are moved to https://github.com/open-telemetry/opentelemetry-go-contrib.
 package main
+
+func main() {
+}

example/opencensus/doc.go → example/opencensus/main.go

@@ -5,3 +5,6 @@
 //
 // Deprecated: Examples are moved to https://github.com/open-telemetry/opentelemetry-go-contrib.
 package main
+
+func main() {
+}

example/otel-collector/doc.go → example/otel-collector/main.go

@@ -5,3 +5,6 @@
 //
 // Deprecated: Examples are moved to https://github.com/open-telemetry/opentelemetry-go-contrib.
 package main
+
+func main() {
+}

example/passthrough/doc.go → example/passthrough/main.go

@@ -5,3 +5,6 @@
 //
 // Deprecated: Examples are moved to https://github.com/open-telemetry/opentelemetry-go-contrib.
 package main
+
+func main() {
+}

example/prometheus/doc.go → example/prometheus/main.go

@@ -5,3 +5,6 @@
 //
 // Deprecated: Examples are moved to https://github.com/open-telemetry/opentelemetry-go-contrib.
 package main
+
+func main() {
+}

example/zipkin/main.go

@@ -0,0 +1,10 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+// Package main provides a code sample of the Prometheus exporter.
+//
+// Deprecated: Examples are moved to https://github.com/open-telemetry/opentelemetry-go-contrib.
+package main
+
+func main() {
+}