private MethodInfo GetConfigureMethodInfo()
 => StartupLoader.FindMethod(this.StartupType, "Configure{0}", this.EnvironmentName, typeof(Task), isRequired: true) !;
 private MethodInfo GetConfigureServicesMethodInfo()
 => StartupLoader.FindMethod(this.StartupType, "Configure{0}Services", this.EnvironmentName, typeof(void), isRequired: true) !;