fix invalid span name

example/main.go

@@ -70,7 +70,7 @@ func main() {
 }
 
 func Serv(ctx context.Context) *fiber.Error {
-	ctx, span := tracer.Service(ctx, "serv", "name of the span")
+	ctx, span := tracer.Service(ctx, "name of the span")
 	defer span.End()
 
 	for range []int{1, 2, 3} {
@@ -86,7 +86,7 @@ func Serv(ctx context.Context) *fiber.Error {
 }
 
 func Repo(ctx context.Context) error {
-	ctx, span := tracer.Repository(ctx, "serv", "name of the span")
+	ctx, span := tracer.Repository(ctx, "name of the span")
 	defer span.End()
 
 	for range []int{1, 2, 3} {