Fix the observable subscription when clicking on a tree node returns an error
Fix the observable subscription when clicking on a tree node returns an error

juvchan/ARMExplorer,mabsimms/ARMExplorer,cicorias/ARMExplorer,projectkudu/ARMExplorer,rhencke/ARMExplorer,projectkudu/AzureResourceExplorer,simongdavies/ARMExplorer,juvchan/ARMExplorer,mabsimms/ARMExplorer,projectkudu/ARMExplorer,cicorias/ARMExplorer,simongdavies/ARMExplorer,rhencke/ARMExplorer,cicorias/ARMExplorer,simongdavies/ARMExplorer,mabsimms/ARMExplorer,projectkudu/AzureResourceExplorer,projectkudu/AzureResourceExplorer,juvchan/ARMExplorer,mabsimms/ARMExplorer,cicorias/ARMExplorer,rhencke/ARMExplorer,projectkudu/AzureResourceExplorer,projectkudu/ARMExplorer,rhencke/ARMExplorer,projectkudu/ARMExplorer,simongdavies/ARMExplorer,juvchan/ARMExplorer