Fixed datadog logs json format issue

pkg/log/datadog.go

+package log
+
+type DatadogLogger struct {
+	logger Logger
+}
+
+func NewDatadogLogger(logger Logger) *DatadogLogger {
+	return &DatadogLogger{logger: logger}
+}
+
+func (d DatadogLogger) Log(msg string) {
+	d.logger.Debug(msg)
+}

pkg/tracing/datadog/datadog.go

 package datadog
 
 import (
+	"context"
 	"io"
 	"net"
 	"os"
@@ -47,6 +48,8 @@ func (c *Config) SetDefaults() {
 
 // Setup sets up the tracer.
 func (c *Config) Setup(serviceName string) (opentracing.Tracer, io.Closer, error) {
+	ctx := log.With(context.Background(), log.Str(log.MetricsProviderName, "datadog"))
+
 	opts := []datadog.StartOption{
 		datadog.WithService(serviceName),
 		datadog.WithDebugMode(c.Debug),
@@ -56,6 +59,7 @@ func (c *Config) Setup(serviceName string) (opentracing.Tracer, io.Closer, error
 			PriorityHeader: c.SamplingPriorityHeaderName,
 			BaggagePrefix:  c.BagagePrefixHeaderName,
 		})),
+		datadog.WithLogger(log.NewDatadogLogger(log.FromContext(ctx))),
 	}
 
 	if c.LocalAgentSocket != "" {