Append tags to existing tags to keep the default ones

metrics/options.go

@@ -61,7 +61,7 @@ func resolveOptions(opts []Option) (*options, error) {
 // statsd.WithTags()
 func WithTags(tags ...string) Option {
 	return func(options *options) error {
-		options.tags = tags
+		options.tags = append(options.tags, tags...)
 		return nil
 	}
 }