Remove kv-namespace-worker

This commit removes the namespace kv worker and related code, now that
we talk over gRPC to the server, and not directly to the DB, we should
not need this anymore.

app.go

@@ -269,20 +269,6 @@ func (h *Headscale) expireEphemeralNodesWorker() {
 	}
 }
 
-// WatchForKVUpdates checks the KV DB table for requests to perform tailnet upgrades
-// This is a way to communitate the CLI with the headscale server.
-func (h *Headscale) watchForKVUpdates(milliSeconds int64) {
-	ticker := time.NewTicker(time.Duration(milliSeconds) * time.Millisecond)
-	for range ticker.C {
-		h.watchForKVUpdatesWorker()
-	}
-}
-
-func (h *Headscale) watchForKVUpdatesWorker() {
-	h.checkForNamespacesPendingUpdates()
-	// more functions will come here in the future
-}
-
 func (h *Headscale) grpcAuthenticationInterceptor(ctx context.Context,
 	req interface{},
 	info *grpc.UnaryServerInfo,
@@ -521,8 +507,6 @@ func (h *Headscale) Serve() error {
 		go h.scheduledDERPMapUpdateWorker(derpMapCancelChannel)
 	}
 
-	// I HATE THIS
-	go h.watchForKVUpdates(updateInterval)
 	go h.expireEphemeralNodes(updateInterval)
 
 	httpServer := &http.Server{