[FIX] fix add gateway form (RT-2773)

fix "Save" button always disabled after "Cancel"
[TEST] e2e: fix login
Merge pull request #1872 from darkdarkdragon/develop-RT-2773

[FIX] fix add gateway form (RT-2773)
Merge pull request #1874 from vhpoet/test/e2e

[TEST] e2e: fix login