fix: fixing import issue

Author: bejjrajesh

src/plugins/metrics_sender.go

@@ -9,6 +9,7 @@ package plugins
 
 import (
 	"context"
+	"github.com/nginx/agent/sdk/v2"
 	agent_config "github.com/nginx/agent/sdk/v2/agent/config"
 	"github.com/nginx/agent/sdk/v2/client"
 	"github.com/nginx/agent/sdk/v2/proto"