feat(performance): Major performance improvements using async v2 from @oberblastmeister (#987)

* start: Working w/ async jobs

* short circuit to using bad finder if you pass writer.

lua/telescope/finders/async_static_finder.lua

@@ -1,7 +1,4 @@
-local async_lib = require "plenary.async_lib"
-local async = async_lib.async
-local await = async_lib.await
-local void = async_lib.void
+local scheduler = require("plenary.async").util.scheduler
 
 local make_entry = require "telescope.make_entry"
 
@@ -29,18 +26,18 @@ return function(opts)
     results = results,
     close = function() end,
   }, {
-    __call = void(async(function(_, _, process_result, process_complete)
+    __call = function(_, _, process_result, process_complete)
       for i, v in ipairs(results) do
         if process_result(v) then
           break
         end
 
         if i % 1000 == 0 then
-          await(async_lib.scheduler())
+          scheduler()
         end
       end
 
       process_complete()
-    end)),
+    end,
   })
 end