Remove duplicated line in editorconfig for dropbox style (#456)

Summary:
Remove `ij_java_names_count_to_use_import_on_demand = 9999` in `.editorconfig-dropbox`

Pull Request resolved: #456

Reviewed By: cortinico

Differential Revision: D56152253

Pulled By: hick209

fbshipit-source-id: 6c01241429eda27e33b5c40637d2a063167f6afb

docs/editorconfig/.editorconfig-dropbox

@@ -63,7 +63,6 @@ ij_kotlin_method_parameters_right_paren_on_new_line = true
 ij_kotlin_method_parameters_wrap = on_every_item
 ij_kotlin_name_count_to_use_star_import = 9999
 ij_kotlin_name_count_to_use_star_import_for_members = 9999
-ij_java_names_count_to_use_import_on_demand = 9999
 ij_kotlin_parameter_annotation_wrap = off
 ij_kotlin_space_after_comma = true
 ij_kotlin_space_after_extend_colon = true