Update prometheus client and go-metrics

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

vendor/github.com/prometheus/common/model/value.go

@@ -129,11 +129,8 @@ func (s *Sample) Equal(o *Sample) bool {
 	if !s.Timestamp.Equal(o.Timestamp) {
 		return false
 	}
-	if s.Value.Equal(o.Value) {
-		return false
-	}
 
-	return true
+	return s.Value.Equal(o.Value)
 }
 
 func (s Sample) String() string {