src/vs/platform/backup/electron-main/backupMainService.ts/BackupMainService/unregisterWorkspaceBackupSync
class BackupMainService:	unregisterWorkspaceBackupSync(workspace: IWorkspaceIdentifier): void {
		const id = workspace.id;
		const index = this.workspaces.findIndex(workspace => workspace.workspace.id === id);
		if (index !== -1) {
			this.workspaces.splice(index, 1);
			this.saveSync();
		}
	}