TUN-3924: Removed db-connect command. Added a placeholder handler for this command that informs users that command is no longer supported.

cmd/cloudflared/cliutil/deprecated.go

@@ -0,0 +1,21 @@
+package cliutil
+
+import (
+	"fmt"
+
+	"github.com/urfave/cli/v2"
+)
+
+func RemovedCommand(name string) *cli.Command {
+	return &cli.Command{
+		Name: name,
+		Action: ErrorHandler(func(context *cli.Context) error {
+			return cli.Exit(
+				fmt.Sprintf("%s command is no longer supported by cloudflared. Consult Argo Tunnel documentation for possible alternative solutions.", name),
+				-1,
+			)
+		}),
+		Description: fmt.Sprintf("%s is deprecated", name),
+		Hidden: true,
+	}
+}