fix an instance of bugprone-move-forwarding-reference

Unless it's guaranteed that `std::forward` always turns into an rvalue
ref, using `std::move(x)`, where `x`'s type is a universal reference, is
generally unsafe. `std::forward` is preferred for these cases.

Bug: 1134310
Change-Id: I1a6eeed1710070d1192e33a9a367b7ea55ad8589
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2443970
Commit-Queue: Oksana Zhuravlova <oksamyt@chromium.org>
Auto-Submit: George Burgess <gbiv@chromium.org>
Reviewed-by: Oksana Zhuravlova <oksamyt@chromium.org>
Cr-Commit-Position: refs/heads/master@{#813216}

mojo/public/cpp/bindings/pending_receiver.h

@@ -74,7 +74,7 @@ class PendingReceiver {
                                      Interface>)(T&&)>>::value>* = nullptr>
   PendingReceiver(T&& other)
       : PendingReceiver(PendingReceiverConverter<T>::template To<Interface>(
-            std::move(other))) {}
+            std::forward<T>(other))) {}
 #endif  // !defined(OS_NACL)
 
   ~PendingReceiver() = default;