HYD-1961 - Selenium test fails to add server
HYD-1961 - Selenium test fails to add server

- My fault. HYD-1699 re-used a button, selenium got confused
- First instance of the button is hidden
- fix by specifying which of the two same-classed buttons to click

Change-Id: Ibb062a51e08a89093718493a67b5527a88abc7ac

intel-hpdd/intel-manager-for-lustre,intel-hpdd/intel-manager-for-lustre,intel-hpdd/intel-manager-for-lustre