Remove gperf dep

Summary: This was probably copied from proxygen

Reviewed By: sandarsh

Differential Revision: D93893191

fbshipit-source-id: 45a90f3272f6b4737860ee1265f0d186ff502f6b

Author: afrind

build/fbcode_builder/manifests/moxygen

@@ -23,7 +23,6 @@ BUILD_TESTS = ON
 BUILD_TESTS = OFF
 
 [dependencies]
-gperf
 folly
 fizz
 wangle