event_handler: Use proper ctx for post fail log

Use the context containing proper information about the event for
logging. Previously, the logged error didn't contain any information
about the event, alert or the involved object.

Signed-off-by: Sunny <darkowlzz@protonmail.com>

internal/server/event_handlers.go

@@ -202,9 +202,9 @@ func (s *EventServer) dispatchNotification(ctx context.Context, event *eventv1.E
 	}
 
 	go func(n notifier.Interface, e eventv1.Event) {
-		ctx, cancel := context.WithTimeout(context.Background(), timeout)
+		pctx, cancel := context.WithTimeout(context.Background(), timeout)
 		defer cancel()
-		if err := n.Post(ctx, e); err != nil {
+		if err := n.Post(pctx, e); err != nil {
 			maskedErrStr, maskErr := masktoken.MaskTokenFromString(err.Error(), token)
 			if maskErr != nil {
 				err = maskErr