Remove edb_server_sets:new

Summary: It's unused, and now that we've settled on transparently using maps, `#{}` looks better on every case.

Reviewed By: jcpetruzza

Differential Revision: D68221072

fbshipit-source-id: 816172acfdff80a5a7f3763c5ee241804368537c

src/edb_server_sets.erl

@@ -28,7 +28,6 @@
     subtract/2,
     to_map/2,
     map_subtract_keys/2,
-    new/0,
     is_empty/1,
     fold/3
 ]).
@@ -40,10 +39,6 @@
 %% -------------------------------------------------------------------
 -type set(A) :: #{A => term()}.
 
--spec new() -> set(none()).
-new() ->
-    #{}.
-
 -spec is_empty(set(_)) -> boolean().
 is_empty(Set) ->
     maps:size(Set) =:= 0.