Handles disposed windows when they are closed while checking windows loop

[netonjm]

This fix, adds in the CommandManager some logic to unsuscribe closed native windows. and also adds a try/catch with logging in current OpenWindowListHandler

Fixes VSTS #999372 - System.ObjectDisposedException exception in Foundation.NSObject.get_SuperHandle()

[netonjm]

@monojenkins rebase

[netonjm]

@monojenkins rebase

[netonjm]

@monojenkins rebase

[netonjm]

rebased!

[Therzok]

@monojenkins rebase

[VladyslavKostin]

@netonjm @Therzok rebase didn't help, something was wrong with "Build monodevelop" task, maybe reopen pr will rid of the issue

[mrward]

Looks like a problem with the code. The build error is:

MonoDevelop.Ide.Commands/WindowCommands.cs(268,14): error CS0246: The type or namespace name 'Exception' could not be found (are you missing a using directive or an assembly reference?) [/Users/runner/runners/2.164.3/work/1/s/monodevelop/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.csproj]

WindowCommands is using Exception but does not have a using System; statement.

[netonjm]

Fixed build issue and rebased! Thank you guys!