hubble: Use GetType() helper in v1.FlowProtocol() to avoid possible p…

…anic

If the event type is unset, or the flow is nil, it's possible that
FlowProtocol could panic. To avoid this, use the GetType() helper method
which is nil safe.

Signed-off-by: Chance Zibolski <chance.zibolski@gmail.com>

pkg/hubble/api/v1/flow.go

@@ -11,7 +11,7 @@ import (
 // FlowProtocol returns the protocol best describing the flow. If available,
 // this is the L7 protocol name, then the L4 protocol name.
 func FlowProtocol(flow *pb.Flow) string {
-	switch flow.GetEventType().Type {
+	switch flow.GetEventType().GetType() {
 	case monitorAPI.MessageTypeAccessLog:
 		if l7 := flow.GetL7(); l7 != nil {
 			switch {