TST: Un-ignore SelectableGroups warning from Ginga dev

Author: pllim

setup.cfg

@@ -15,8 +15,6 @@ filterwarnings =
     ignore:Marker set named:UserWarning
     # https://github.com/ejeschke/ginga/issues/1033
     ignore:There is no current event loop:DeprecationWarning
-    # https://github.com/ejeschke/ginga/issues/1034
-    ignore:SelectableGroups dict interface is deprecated:DeprecationWarning
 
 [flake8]
 # E501: line too long