remove superfluous include directive

Summary:folly::fibers does not use folly::MoveWrapper anymore, so no need to
include that header file.

Reviewed By: yfeldblum

Differential Revision: D3169374

fb-gh-sync-id: 2409b46156843fb0a1454b560c42186f1c412988
fbshipit-source-id: 2409b46156843fb0a1454b560c42186f1c412988

folly/experimental/fibers/FiberManager-inl.h

@@ -19,7 +19,6 @@
 
 #include <folly/CPortability.h>
 #include <folly/Memory.h>
-#include <folly/MoveWrapper.h>
 #include <folly/Optional.h>
 #include <folly/Portability.h>
 #include <folly/ScopeGuard.h>