Could not auto close unsaved editor when delete

The newly added "delete" feature #343 works well when we try to delete unchanged files. However, if we try to delete file with unsaved changes, the editor will not be closed and will looks like below:

This is not consistent with native file explorer's behavior and may also cause user lose their changes before deletion. However, this part is hard to fix due to API limitation, since many needed functions are encapsulated within the implementation of VS Code built-in commands. If microsoft/vscode#107566 could be solved, we can fix this problem easily.

Beginne mit der Löschfunktion aus Issue #343 und reproduziere das Löschen einer Datei mit ungespeicherten Änderungen in der VS Code-Erweiterung. Lies microsoft/vscode#107566, um die API-Einschränkung zu verstehen; abgeschlossen ist die Aufgabe, wenn der Editor sich konsistent zum nativen Verhalten des Datei-Explorers schließt, ohne ungespeicherte Änderungen zu gefährden.