fix: delete unused var and const (#3294)

Signed-off-by: hwdef <hwdef97@gmail.com>

plugin/forward/forward.go

@@ -199,15 +199,6 @@ var (
 	ErrCachedClosed = errors.New("cached connection was closed by peer")
 )
 
-// policy tells forward what policy for selecting upstream it uses.
-type policy int
-
-const (
-	randomPolicy policy = iota
-	roundRobinPolicy
-	sequentialPolicy
-)
-
 // options holds various options that can be set.
 type options struct {
 	forceTCP  bool

plugin/forward/proxy.go

@@ -80,6 +80,5 @@ func (p *Proxy) start(duration time.Duration) {
 
 const (
 	maxTimeout = 2 * time.Second
-	minTimeout = 200 * time.Millisecond
 	hcInterval = 500 * time.Millisecond
 )