如何解决“Waiting for another flutter command to release the startup lock...”

执行 Flutter 包管理相关命令时有可能遇到 Waiting for another flutter command to release the startup lock... 这样的错误，可尝试杀死所有的 dart 进程解决：

// Linux
killall -9 dart

// Windows
taskkill /F /IM dart.exe

参考：

• Waiting for another flutter command to release the startup lock