feat: update slack-go dependency

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

@@ -0,0 +1,30 @@
+package socketmode
+
+import "encoding/json"
+
+// Event is the event sent to the consumer of Client
+type Event struct {
+	Type EventType
+	Data interface{}
+
+	// Request is the json-decoded raw WebSocket message that is received via the Slack Socket Mode
+	// WebSocket connection.
+	Request *Request
+}
+
+type ErrorBadMessage struct {
+	Cause   error
+	Message json.RawMessage
+}
+
+type ErrorWriteFailed struct {
+	Cause    error
+	Response *Response
+}
+
+type errorRequestedDisconnect struct {
+}
+
+func (e errorRequestedDisconnect) Error() string {
+	return "disconnection requested: Slack requested us to disconnect"
+}