feat: update slack-go dependency

vendor/github.com/slack-go/slack/socketmode/deadman.go

@@ -0,0 +1,31 @@
+package socketmode
+
+import "time"
+
+type deadmanTimer struct {
+	timeout time.Duration
+	timer   *time.Timer
+}
+
+func newDeadmanTimer(timeout time.Duration) *deadmanTimer {
+	return &deadmanTimer{
+		timeout: timeout,
+		timer:   time.NewTimer(timeout),
+	}
+}
+
+func (smc *deadmanTimer) Elapsed() <-chan time.Time {
+	return smc.timer.C
+}
+
+func (smc *deadmanTimer) Reset() {
+	// Note that this is the correct way to Reset a non-expired timer
+	if !smc.timer.Stop() {
+		select {
+		case <-smc.timer.C:
+		default:
+		}
+	}
+
+	smc.timer.Reset(smc.timeout)
+}